You can order stuff from www.uscomposites.com. I've found them to have the best prices and best quality stuff.
As far as the spray on stuff goes I wouldn't even mess with it because it's so messy and you can't control it like you can paint. YOu will get fiberglass resin everywhere and on everything...not to mention needing the right equipment. A regular spray gun will not spray enough material to do anything worthwhile...stick to hand lay up..it's much easier to control and work with.