Here's a link that will give you loads of info. They will make the quilts for you, but also have lots of how-to on their site, as well as a well detailed book on how-to is available.
http://www.toocooltshirtquilts.com/
Their technique does not use a stabilizer on the t-shirts and IMHO gives a far nicer finish, than those that are done with stabilizer and fabric sashings.