hmm i don't know if this is within the scope of this forum but i'll give it a shot.
Which company do you think will be good and willing to take a third year undeergraduate for internship anywhere in the US?
Larger companies are more able than smaller ones. Learn how to write a resume and send it to companies that you would like to work at. Tell them what you are able to do and ask if they have an opening. If you can find someone in the company to call on the phone, that is even better than the resume.