Where can I find the rules on if I am a nonresident or a part-time resident?
Residence: GA until 6/2008, NY 6/2008-now as a graduate student (so I live and work in NY).

I am a Nomad so I wanted to be clear on the rules. Thank you in advance. I Googled this topic and you kept coming up (though I am still confused), I appreciate Your Advice!

On F1/OPT you are exempt from residency for 5-years. You must file non-resident tax return Form 1040NR or 1040NR-EZ and Form 8843.
Read: Your U.S. Tax Return: U.S. Tax Filing Requirements for Non-Residents

You are part-year residents for both Georgia and NY state. If you are living in NY city, you ae NOT a NYC resident for tax purposes due to your status as a student.

File GA Form 500 and NY Form IT-203 for the respective state returns.