Thanks, guys! In addition to Byron Walker and John Cannon, mentioned above by Clay, let me add a few others I recommend checking with (in no particular order):
Dan Bradbury of Bradbury Books and Beyond (www.bradburybooks.com
), Andy Greget (no email or web presence, but a great inventory), Kenna Thompson (www.ktmagic.com
), George Daily (no website but active on eBay and a member of this forum), Mario Carrandi (also a member of this forum), and Ted Bogusta (www.martinka.com
). I've purchased books from all the above and have been happy with my purchases. Many brick and mortar shops also have a shelf of used books. Denny of Denny and Lee does, for example. I also recommend watching the magic book sales on eBay for occasional bargains and using www.bookfinder.com
to check for general public titles.
There are plenty of source for good used magic books. We typically discount good used copies of still in print titles by 20%, more if condition not good, so used books can be a cost effective way to build a good working library.