I moved to a new town and new school in September 06. When I got there the first day I wanted to make a lot more friends than at my old town because I looked at it as a fresh start.
For the first couple months I was really quiet and no one really talked to me unless we were in groups working on projects. I was really scared to start conversations with people for fear of rejection. And yes the few times I tried to join conversations I was rejected. It's not that people don't like you when you're new, it's more that they're scared to add any new friends to their group.
Knowing that I was really good at hockey, I thought maybe if I played for the school team or town team I would be able to make friends. Well I tried out and made it and ended up being one of the best in the grade. That helped a tremendous amount because now I sat at lunch with people who played hockey and didn't have to sit with people who didn't like me and didn't have anything in common. Sports and other interests are great places to make friends at. Now being in my 2nd year here, I have a lot more friends than I could've imagined. I'm still not 100% welcome with all people, but I realized I don't need them.
Yes, you're probably going to encounter rejection and loneliness at your new school, but over time it will pass and you'll start becoming friends with people. You're probably never going to be friends with all the popular kids there but you can certainly find worthy ones.
Good luck, and remember you need to find a shared interest with people and put yourself out there to be friendly.