GRC monitor / SOD control

Dear Expert,

This is my first post here at SCN.

Our company recently implemented SAP 6.0 over from AS400.  After almost a year of settle down, I'm start looking for GRC monitor and our SOD control because we will be subject to audit by the year end.

Would anyone of you please let me know what is the best solution to implement GRC/SOD?  What kind of software that I need? and what is the requirement?

Thanks

MV