http://www.mailleartisans.org/weaves/ - this is the biggest resource out there - it's huge, but it's all there. I'm happy to help anyone having problems navigating!
http://cgmaille.com/- excellent cgi renders of a small number of weaves
http://theringlord.org/derakoninstructions/inst.html - Derakon's library (this has moved)
http://www.davidchain.com/byz_tut1.html - David Scott Plumlee's byzantine tutorial