Good lord no, if you value anything below your hairline do NOT get anything with a displacement of over 500 cc to start off.
It really helps to know the mechanics of a standard transmission automobile, specifically how to clutch properly. Otherwise, you could be stuck at the front of an advance green, and quite embarassed. Personal experience with that? No, not me...
For cheap and start off, I would personally recommend a '75-85 Honda CB250, just to learn how to ride. Plus they're only $500-1000. Then when you've got everything PERFECT, beyond the shadow of any doubt, go for a more powerful bike.