Man, really don't worry about being rejected....it's a part of life. The only way to find out if she is into u is go up and make coversation with her. Rejected or not, the hard part is over. Breaking the ice is the most difficult part for most of us. I had the same problem. I was friends with a girl who had a very good looking friend who i like for quite a while. I asked her if her friend knew me. She came back and reported that she knew me and wanted to talk to me and get to know me. And after all that time being afraid to talk, she wants to talk to me and get to know me as bad as i want to talk with her. Still, i was afraid, but i had to make my move before i lost my chance. Start out casual, be nice for some time then act like u dont want to talk to her ( to an extent, if not done right, this can ruin it all) after that is over, start hanging out with her, taking her to movies and whatnot. Before u know it, she will like u a lot. ask her out and its smooth sailing from there.
GOOD LUCK MAN.....tell us what happens