http://mytargets.com/
http://targetz.com/
Both have a bunch of good ones.
Find a few that you like and print them out.
Take them to the range and shot them.
Figure out which ones you like.
The ones you thought were great when sitting at your computer are not likely the ones you'll like at the range.
Once you've decided the 'keepers', print out one of each.
Take them to Staples, and print out 100 of each.
Copies are 10 cents apiece for black&white; printing them at home will drain a cartridge pdq.