hi and welcome, goat showed me a very cool bike with disc brakes recently, full suspension with an amazing motor, was pricey though and prebuilt i think. but like he said theirs tons of ideas. if you want to build one yourself i think you'll need a jack shaft kit to keep your disc brakes that usually come with the bikes (sickbikeparts.com sells them starting at $150+shipping) but it lets you do a lot more with the motor with out going full throttle all the time since you can use all the gears on the bike like you normally would.
heres some of the links iv'e been shown in the last few days
i'm quite new to this myself so i don't know nearly as much as most of the other people here, many of them are very smart and helpful though, have fun and welcome again