I came in Us in 07.14.2006 with H2b visa... I filed for 2006 federal and state taxes.. . I left US in first of July 2007. Am I eligible to a full refund, including federal, medicare, social security taxes? How can I file from abroad ?thank you.

You are NOT eligible for any refund of your Social Security and Medicare taxes.

You may get a partial refund for the income taxes.