Looks like you're new to this game: using backtrack 4 with rtl8192e wireless card.
Obviously, if you can get internets, your card is working. If you're using your card for internets, you can't put it in monitor mode at the same time. That would just be ridonkulous, and should have been quite obvious to you. Check the compatibility list put forth by the developers of aircrack-ng. It's on the internets. I know this because I search before I post. If your card isn't there, then chances are you'll need to get yourself a new, compatible card.
The answers are out there, waiting for you to find them. When/if you do find them, c'mon back and post how you got it to work in the HCL forums.
And, since I'm nicer than some other people on the forum, I've included a link.