Hi
I filed 1040 NR in my 1st year (2008) and filed 1040 by a tax guy in my 2nd year (2009). Now its time to file tax returns. I am an exempt student so I am not a resident alien.

My question:
1. I know I have to file 1040 NR now.. But do I need to do amendment for my last year's mistake by filing 1040X?
2. I found last year that the tax preparation guy did not pay me all my money from IRS. He kept back at least $600.
So if I do an amendment I will ave to pay that extra $600 from my pocket which I never received. So I am worried.

Thank you in advance for your advice.

Yes, you will file 1040X along with properly done non resident tax return and form 8843 for 2009. You will pay any tax due with interest.
Your U.S. Tax Return: U.S. Tax Filing Requirements for Non-Residents (http://taxipay.blogspot.com/2008/03/us-tax-filing-requirements-for-non.html)