I'll jump in with a warning about TyTy Nurseries and all of it's affiliates. Read the attached thread for some laughs, as well as strong warnings about these folks.

I've ordered from Bluestone Perennials and have always been satisfied.

Here is a link that might be useful: The worst of the worst

There are definitely a few companies to be avoided at all costs. Rhizo names one - another is any company associated with Gardens Alive!.....Michigan Bulb, Gurneys, Springhill, Henry Fields, Brents Bulbs, etc. They have a reputation for very poor plant quality, mislabeling, making up plant names and terrible (read nonexistant) customer service. But they're cheap!

But there's many excellent mail order companies out there as well. It's always a good idea to get feedback or info on them before placing any orders and the Garden Watchdog is a great resource for that

Here is a link that might be useful: Garden Watchdog

I like ebay, theres a lot of odd finds.

I ordered from Farmers seed. I did not know about garden watchdog at the time. I am very happy with the bulbs - most of them are coming up. I am somewhat happy with the perennials, about 1/2 of them are alive. (I'm about to try to get the dead ones replaced - I figure I'll give them about another week before I decide the dormant ones didn't survive). But am disappointed in the roses. It appears that only 1 of my climbing roses is even 1/2 alive. And I don't think 1 of the rose of sharon bushes is alive But I don't know how to tell or how long I should wait to see if the stem will turn green and produce sprouts.
-Kitty