I don't have any suggestions for vanities, but if you're doing a traditional bathroom in whites and blues, I'd go with a white or blue tile for the floor. You could use a hexagon shaped tile that was popular in the era of your home, you could use white tile with a boarder in blue (like a rug outline?) or you could add some of the same blue accents that match the border of your wall tile.

I don't know of a good online site for vanities. pottery Barn and Restoration Hardware sell some, but IMO they are a little pricey.

With respect to the vanity flooring...you could go black on the vanity and then white on the floor. I like lukkiirish's suggestions for a floor; white tile with small blue (maybe hexagon?) inset.

If you want a white/gray marble look in porcelain tile, look at American Olean Catarina Coliseum White.

Here is a link that might be useful: AO Catarina Coliseum White

Thanks everyone!

bbstx -- I like the porcelain tile you pointed to me and there is a dealer close to my home so I'm going to go look at it!

andreadeg -- I was thinking just what you said -- a darker vanity with a lighter floor. I did look at PB and the vanities but too expensive!

lukkiirish -- yes, I like the idea of using the accent tiles on the floor. I think they'd look gorgeous with the porcelain tile that bbstx suggested.

I purchased a Restoration Hardware vanity after I looked around and simply could not find what I wanted anywhere else. At the time they were having a bath sale (20% I think) and I believe it happens once or twice every year. If you are not in a big rush, you might wait for a sale. It's possible Pottery Barn might also do a similar sale.

Do it best has a lot of vanities, I have never seen them in person so I do not know the quality but there are a lot.

Here is a link that might be useful: Do it best vanities

Thanks again --I found a few choices at "fuacets direct." But I'm not with familiar with the site, so more research. I didn't realize finding a vanity was going to be so hard...

I agree that finding a vanity was the one thing that surprised me with how difficult/expensive it was. In the end I ordered a sink cabinet from a Kithen & Bath store for about $750 for 22 inches wide. Here are a lot of the links where I found possibilities. Ordering from a cabinet company you can see the wood samples and speak at length with the salesperson who'll know about different woods, stains, etc. At this link to their site you can go to Contact and ask for a dealer hear you. Most I saw at these links come with a top already but some are relatively inexpensive and you could use the material you selected and give the top you don't use to a Habitat for Humanity store. The cabinet company my local store ordered from was Executive Cabinetry (used the Green Cabinetry line) & it is great quality. But it takes 8 weeks to come FYI. I lived without a vanity for a while after the rest was finished.
I also love my American Olean porcelain tile so that is a great suggestion.

Links to vanities online (if the links are busted try just deleting everything in the URL after .com)

http://www.thebathroomdepot.com/bathroom/Under-30-Vanities-p-2-c-492.html

http://www.simplyvanities.com/bathroom-vanities/single-sink-vanities/newport24inchvanity1.cfm

http://www.ronbow.com/prodlist.php?cid=16

http://www.costco.com/Common/Category.aspx?whse=BC&Ne=5000001&eCat=BC%7C114%7C1240&N=4000377+4294901498&Nr=P_CatalogName:BC&Ns=P_Price%7C1%7C%7CP_SignDesc1&topnav=

http://www.homedepot.com/webapp/wcs/stores/servlet/ProductDisplay?storeId=10051&langId=-1&catalogId=10053&productId=100649900&N=10000003+90043+500278+4294921356

http://www.homedepot.com/webapp/wcs/stores/servlet/ProductDisplay?storeId=10051&langId=-1&catalogId=10053&productId=100646015&N=10000003+90043+503378+4294921356

http://www.hometodreamhome.com/Wood-vanity-base-with-two-doors-and-pullout-bottom-for-use-with-5493-washbasin-235493C01-Prodview.html

http://www.modernbathroom.com/width-under-30_71_0.html
http://www.decorplanet.com/SearchResults.asp

http://www.all-bathroom-vanities.com/eudevainwhoa5.html
http://www.all-bathroom-vanities.com/mosivadr77.html

http://www.everyvesselsink.com/CO24-CO30-CO36-2522-3122-3722-EMP2019.html

http://www.everyvesselsink.com/N-2522-3122-3722-4322-4922-NM-EMP2030.html

Here is a link that might be useful: Executive Kitchens source for vanity cabinet

And a hint when searching sites online for a vanity: type the size in the search box so only the size you can use will result.

30" vanity

for example.