I work in NY and live in NJ. It seems like I have been doing my taxes wrong for several years - owing NJ and paying over $300 a year. I had help this year and found out I owe NJ nothing and I actually get a refund. I want to know how can I get back my money from the previous years I sent them money?

Yes, you can amend your return for 2004, 2005 and 2006.

For 2003 and earlier, it is too late due to the three-year statue of limitations.