I got private loans through Sallie Mae, and they sent the cheque directly to the university. However, they're unlikely to grant you a loan unless you have significant credit history - I had to get my mum to be a co-signer - or if they do the interest rate can be incredibly high.
I don't know if I'd actually recommend the company because they're pretty horrid when it comes to customer service. However, I do know that they offer private loans and send them directly to the university, so you can look into it. Check out the American Students Assistants,
http://www.asa.org/default.aspx, they have a pretty substantive overview of funding for students. Also, see if your university has any guidance for international students; the international department at mine was really helpful with all of my financial queries (possibly because they're so eager to get our money!). You can also try to get loans from you bank in the states, and this would be put directly into your account rather than sent to the university. Again, this will be difficult if you don't have a lot of good credit history.