1998 Buick Regal GS ABS Control Module

Where is the ABS Control Module Located and how do you get to it?
Is there any diagrams etc?

Did you get this problem fixed? My sister's ABS and trac quit working, and the shop wants $500 for replacing the computer..

Please let me know what you did to fix your problem, where the module is at, and any other pertinent info.

I aprreciate it!

Colin