In physics graduate school you can get a Master's Degree in about two years or a PhD in about six years.  In PhD programs, typically your tuition is paid and you receive a stipend to live on.  Applications are typically due in the late fall. 

A great place to start looking at graduate programs in physics is The Grad School Shopper.  You can also consult U.S. News Physics Grad School Rankings.

Underrepresented minority students should check out the APS Bridge Program. 

You may also need to take the GRE so here are some resources.

• Graduate Record Examination Guide
• Physics GRE Sample Test Solutions
• Physics GRE Discussion Forums