Right before my baby was born I also joined a few other sites.
Sites like Parenting Weekly, Fit Pregnancy, Planning Family have lots of great information and offers like coupons and free trial magazine subscriptions.
Pampers and Huggies both have a rewards program where whenever you buy their products you earn points towards stuff like Shutterfly credit. Since new parents are going to be buying diapers and wipes anyway they might as well be getting something out of it. Both Huggies and Pampers also gave me a free trial pair of diapers...free is good.
I also get a lot of coupons from Enfamil, Gerber, & Similac. I am not giving my baby formula yet, but I'm sure it will come in handy at some point.
If you are a mom take a look at what these sites have to offer. There's a lot out there, take advantage of it.