Redbuds do fine, both the normal green ones and the reddish 'Forest Pansy'. Because they aren't good at being propagated, nor at living in pots, they can be hard to find. Since they are natives, if you can find a local grower or a specialized nursery, you should be able to find them. They do reseed from an established tree, for the green-leafed, so you can probably find babies under an established one, if you are willing to wait for it to grow - plant it promptly. I dug one out of a friend's garden about 7 years ago and found a 'Forest Pansy' at a spring Plant Sale/Show in the Asheville area last year.

Dogwoods are another possibility - the C. kousa, while it flowers later, after leafing out, withstands the anthracnose better than C. florida - there may be resistant selections out there now. Or, you can grow both, enjoy the extended bloom time, and hope for the best, depending on conditions in your area.

The best cherry is probably 'Kanzan' - the W in Kwanzan is someone's typo from years ago, perpetuated by familiarity. They can be prone to disease and borers, so I would check on reliability in your area.

Serviceberry is another possibility, esp if you can find a single-trunked form. All the above flower in the spring, and the dogwoods and serviceberry fruit, which the birds usually eat - you can try to beat the birds to the serviceberry fruits.

Some of the viburnums will grow tall, and can be trimmed up into small trees - some of these also bear fruit. Hollies, while slow growing, can also be limbed up into small trees, although you need a male with several females to get berries. And most of the deciduous magnolias will grow into small trees - the flower color and the form of the eventual tree can vary from white to red to purple to yellow, and from widely spreading to quite columnar, so it depends on what you want. Elizabeth, a yellow one, has a nicely spreading form. Some will also give sporadic flowers through the summer.

For summer-flowering trees, a cultivar of crape myrtle could be nice - you would have to select for color and for eventual height as some are small - less than 3' - and some are tall - over 30'. Vitex is another pretty, small, summer-flowering tree - while it's small, you can dead-head and get several flowerings per summer, but once it grows too tall to clip easily, you will still probably get 2. Mine are flowering now, and, if I trim them will flower at least twice more, but only once if I leave them. After 3 years from 1-gallon pots, both are about 5-6' tall. Butterfly bushes (Buddleia species) can also be limbed up into small trees, although the flowering won't be quite as profuse as one constantly trimmed back would be - there are other, attractive species than the common B. davidii.

Hope these give you some ideas. I would check the ones with questions; try checking with your county extension agent's office - they should have a list of recommended varieties, and maybe a list of those that DON'T do well. I can't help with local nurseries, but maybe someone closer can help. Niche Gardens, Woodlanders, Meadowbrook/We-Du Nurseries are all specialists for natives, which do mail-order. Since a number of the above are natives, that may be a starting point.

Deborah, my vote is for the vitex. I have several varieties here although one is a tropical and stays potted to live in the garage or house in winter.
I planted mine here in '04 and by '07 most are 12' tall now.
They take up a good bit of room so you have to have an area about 10'-12' wide. Usually multi-trunked and they do need annual trimming, if only to get the water spikes out(straight branches from low on the trunks that grow straight up 6-8' before blooming.
If you plan to plant under it, plant your perennials as you plant the tree because vitex roots grow close to the ground surface.
It likes a good bit of water but also prefers a well drained area.
They are wonderful screens, dense but airy leaves in summer. Nice for Christmas lighting if you can leave the lights in place.
You can clip them down to about 3'tall and expect it to grow back to 6-8' in summer but it isn't necessary. I just clip back most of that years growth concentrating on removing a lot of the interior growth. Like a butterfly bush it blooms on new growth.

It attracts all kinds of bees and wasps that are amazingly calm when feeding. Guess because there are so many blooms there's no competition.

I have noticed that japanese beetles love it for perching. They don't eat the leaves or blossoms..they just mate there. Easy to spot and catch.

The other one I love is the curly willow. I got slips from a friend whose great grandmother's yard was being bulldozed for a housing development in Waxhaw. That was in 03' and the triple tree ( I loosely braided the three rooted slips) is just over 20' tall now.
The winter structure is dazzling against the sky. It doesn't weep like common willow and I don't think the roots are as invasive to water sources as common willow.

I can get you some slips if you want to root them. Takes no time at all to root.

'Forest Pansy' & most of the other redbuds one sees (in the wild & in nurseries) are Eastern Redbuds (aka Canadian Redbuds). Although they give a wonderful spring show, their foliage starts looking really ratty by midsummer, so it's best to plant them where they can be viewed at a distance.

A great alternative is the Texas or Oklahoma Redbud. It flowers just as spectacularly as the Eastern variety, but the leaves have MUCH more substance & continue to look shiny & healthy throughout the summer. Redbuds with white blossoms are available in both the Texas & Eastern varieties. I worked with a local nursery to special-order Texas redbuds in both colors. I've since seen them available here each spring, altho in small quantities.

Fringetree is another flowering tree that doesn't grow very large. There are 2 varieties -- American & Chinese. Both do well in the South but, IMHO, the Chinese is more beautiful. Both are generally available at good nurseries in my area.

My favorite small flowering trees are two that you'll probably have to search out on-line: Sophora affinis (Eve's Necklace) and Sapindus drummondii (Texas Soapberry). Both are very elegant little trees with good fall color & with an open structure that makes them interesting even after they lose their leaves. Eve's Necklace has ferny foliage, & its flowers are lavender racemes that remind me of miniature wisteria blooms. There are other varieties of both Sophora & Sapindus that are more readily available. Those may be just as impressive, but the 2 I've named here are the only varieties I have experience with.

Don't forget the Carolina Silver Bell. Great small tree. The fringe tree is a great one too (as stated above).. Don't forget the Service Berry and the Diabolo Ninebark. Ninebark is has a dark foliage and blooms pinkish-white button like flowers in mid summer. VERY showy and extremely hardy. It gets 5-6 tall and 4-5 wide. Do a search for Physocarpus opulifolius "Mondo" for the ninebark. Check out the box stores for some of these. I'm always surprised at the varity they have. You may want to wait till fall to plant and the box stores will have a better selection then too. Good luck.

Thanks for all the great suggestions! We spent a good part of the weekend tree shopping. We ended up getting Kousa Dogwood, Yoshino Cherry, Serviceberry, red Crepe Myrtle and Lavender Twist Redbud. We would very much like to get the Chinese Fringe tree as well but haven't found one locally yet. I may break down and order one from the net.

Love the Eve's Necklace but a search in town & in the net produced nothing. Must be a hard to find tree. But I'm going to keep my eyes open for it. I've never heard of that one before & it looks like a great tree.

We'd also like to find a dark purple Crepe Myrtle but haven't had luck there either. Everything is the light purple. I might replace that with the Vitex Dottie recommended. I'm kicking myself because I saw that at Pikes 2 weeks ago for 50% off and now their all gone.

We've got all of these trees sitting in their nursery pots in part shade & will wait till late Sept., early Oct. for planting. We really need some relief from the blazing hot sun for us and the flowers I've got planted. With no trees in our backyard, even the full sun flowers are frying in this drought.

I was so happy last night to see all the birds that were attracted by just these few. The hummingbirds love sitting in the Cherry & Serviceberry. Thanks again for all the good suggestions. We have room for a few more please keep them coming.

Over here in Raleigh there is a used book store that has the most spectacular dark purple Crape Myrtles in the parking lot (Readers Corner near NCState). Looks like grape Koolaid. But they only bloom for a few weeks and then they are done - many of the pinks and whites will bloom much longer if not all summer and into fall.

Fringe Trees are around but you tend to see them for sale while they are in bloom in the spring.

Now is the time to shop for deals. But you need to set up a shady area to nurse them through this drought. The larger grower/nursery operations that ring the Triangle are dumping all their spring stock to make room for fall crops. One place near my job has stuff for a dollar!!!