I just put on a new set of 4 wheel disc brakes on my 68 and the 15 inch rims dont fit even though when i bought them they said they would, i was wondering if they made a 16 inch rally wheel and where would i find them.

First of all, welcome to Team Camaro, Try this place, they should have what you need. You might find a place closer to you but, this is a nice place to start...:D
http://www.stocktonwheel.com/rally_wheels.htm

Be careful. I tried to find a 16" wheel to fit over my brakes and found that the 16" wheel has the same center section as the 15" but they put a larger diameter rim around it. You actually won't gain any appreciable clearance. If you do find one I would like to know about it.
I believe the exception might be the billet aluminum wheels distributed by http://www.wheelvintiques.com/

Wheel Vintiques sells many sizes of ralleye wheels. They are Billet not stamped steel, however. Be prepared to fork over your next born for them as they are overly expensive! They are very nice wheels none the less.

Bob