How to prevent excessive use/site grabbing/downloading?
 

Basically one IP has been very busy grabbing my whole site... now I can block that IP, no biggie, but you can only do that when you notice the volume...

my question now... can I set an IP/user limit of X GB download and afterward block access to my site? any points on how i can do that would be appreciated.

If I'm not mistaken and understand what you are saying correctly, I think Phantom Frog will do this.