SilkRoad,
She cannot get tourist visas for her parents no matter what her status, be it non-immigrant, LPR, or citizen. They have to apply for and get their own visas based on their own circumstances.
The most that anyone can do to help them is provide any necessary financial support and, to a lesser extent 'cheerleading' assistance by supporting the credibility of their application. You may be as useful as your wife in that regard, perhaps more useful than her with regard to the financial support.
See 9 FAM 41.31 Notes, N1 through N4 for more information on the B visas.
Yodrak
QUOTE(SilkRoad @ Sep 7 2006, 09:24 PM)

I understand that my foriegn wife would need to wait for her USC before applying to bring relatives to the US. However, will it be any easier for her to get turist visas for her parents once she has a green card ? Thanks.