My very quilty friend that makes a lot of t-shirt quilts uses French fuse. In fact, I'm about to embark on making one myself as a Christmas gift and she brought me the French fuse to use. Said it was far superior to anything else on the market and I trusted her since she's made so many. She has a great tutorial on her blog site which lays out exactly how to make a t-shirt quilt.
http://b-quilts.com/blog/