A friend of mine is in the middle of repainting his 20 year old Trek touring bike.

First, he sanded off all the old paint and primer using paint stripper (or was it paint thinner, or are they both the same thing?). It took about 3 weeks to do this.

A proffessional painter told him to use spray cans and told him which brands of primer and paint to buy, I forget the name brands but will find out and let you know.

He has the frame primed now and is ready to paint. So far it looks really good- totally blew my theory that amateurs have no business painting bicycle frames.