I have mod_bwlimited installed. I would like to throttle an account on the server that is using alot of bandwidth.

Is there a tutorial or a help on how to configure this? Is there something in CP that I can do ?

You need to install mod_bandwidth which will let you impose all sorts of limits on accounts (such as max of xx bps / minumum of xx bps / xx connections / xx GB every xx days / transfer files over xx MB in size at a max of xx bps etc...)

use mod_throttle instead
http://www.snert.com/Software/mod_throttle/