There's lots of great resources on the web, like the Arthritis Foundation at arthritis.org. RA specific informaiton is at
http://www.arthritis.org/disease-center.php?disease_id=31
The important thing to keep in mind is that most RA cases are very treatable. There are lots of medications available, and more are more being introduced every year. Cost can be a big issue depending on her insurance, as some of the options are quite expensive; there may be hard decisions between new, expensive medications and older, cheaper ones.
There's a lot of people here that that have RA or something similar, so you've come to a great place to get questions answered.