Many.

http://www.flytrapshop.com/
http://www.flytrapranch.com/
http://www.californiacarnivores.com/
http://www.carnivorousplantnursery.com/
http://www.flytraps.com/

All are good stores. FlytrapShop runs a really great forum for flytraps, the mention of which is banned on this forum for some reason.

FlytrapRanch is ran by an awesome guy and sells neat foam pots, which are great for protecting plants from temperature extremes.

California Carnivores is the biggest VFT store in the US and has an excellent book for sale that I suggest highly (it's the definitive book on growing carnivorous plants).

CarnivorousPlantNursery sells lots of interesting varieties at good prices (and usually gives away a free plant with every order), but sells them unpotted. If you have good potting media and a pot ready for them, you might look into them, here are the 2 I recently got from them:
http://kita.ath.cx/plants/04.08.09/goldstrike.jpg
http://kita.ath.cx/plants/04.08.09/redpirahna.jpg

They aren't kidding when they say "small", btw. Those are 3.5" pots. The plants are about the size of my thumbnail.

Cooks' Carnivorous Plants has really good pricing but some people have reported iffy plants from him. I haven't had any problems other than a scare with an overly-trimmed and dormant Binata Sundew. This is my most recent plant from him, a B-52 Venus Flytrap:

http://kita.ath.cx/plants/04.16.09/B52.jpg

California Carnivores charges a $4 handling fee for any order. If your just getting one or two plants don't order from them, it cheaper to order from flytrap.com and the plants the same quality, which is very good. Consider joining the flytrap.com forum, it is much more organized and has less intrusive adds.

Sarracenia Northwest is a great place as well (my favorite):

http://cobraplant.com/index.php