What a terrible thread. How about posting some more information along with your question? What do you mean ranking in USA? You mean on google.com vs google.xx? Where do you rank now? What is your site about, and what kind of SEO have you done already?
Try to get backlinks from USA local website & directories. It helps you to get ranking & local visitors for your website
POst your links in huge volume in us based local directories. and also insert your local maps and local forums. It will help a lot.
Hi.........! this suggestion not mine but deeply appeals to the heart and seems for you to go in a right way, and don't look here and there.
Simple answer, find some good USA based sites in your topic area and see what or how you could get a link from them
Search out local USA directory,articles websites and resources.Submit your website into it. Submit your website in local business listing. Find out some relevant website related to your business and based on US and list your website their.