They did give a bunch of codes out to partner sites... IGN, Curse - there is a post about it on SWTOR.com (or create a post and ask, someone will send you in the right direction after 10 trolls call you stupid) I would link it but I can't get to any game sites at work, blocked.
signing up this late your probably going to be in the Sunday 10 AM CST start time "wave" but you still might be able to get a beta code from one of these sites.
Hmmm I googled and although I cant go there as its blocked, I got this link as a result. um might work..?
www.curse.com/betas/swtor-na