There are many Hip-Hop and R&B artists:

Usher, Beyonce, Marques Houston, Omarion , Chris Brown.

Grups:

b2k, B5, G Unit

If you are interested you can download a lot of songs.
Ther are a lot of artists. You can view more information in:
http://www.ejams.com
There are differents news, new songs.