I found a whole bunch of pipe with my friends house and he said I could use it. It's probably enough to make a crappy bike. What do I need for framebuilding? How do I know when my frame is strong enough to support a normal persons weight?
Frames above kid's bikes are made out of good quality aircraft tubing or better. People do make stuff like low riders out of conduit, you might try to find a copy of the Atomic Zombie bicycle builder's Bonanza at your local library or order it off Amazon. Also check out their site. They do a lot of interesting things in marginal quality pipe.