My wife is on a dependent visa for my Non-Immigrant OA visa.  Has to do three month renewal.  What docs does she need to take to immigration office?

I assume you are writing about a report of staying longer than 90 days in the country. It depends upon the office she will be reporting to. At most offices it would be a completed TM47 form and her passport for the first report.

 

Yep. Looks like you are asking about a 90 day report.

It is not a renewal.

As Joe said above, passport and TM47 form usually.