Bro, I so feel you. Seriously. Spring seems to have everyone horny.
Thankfully, I've narrowed my original 5 down to 2. Do what I do: go on very simple, cheap dates with each one originally, and then work up from each one... shred them off one by one, until you've found the girl who you like most/is most receptive to you (hopefully the one you end up with will be both!)...
Here's a good rundown of how multidating can help: http://www.outpostnine.com/editorials/multi.html