I live in GA. I know I can deduct the mortgage interest. But should I also download a SC State tax form and deduct the state property tax I paid as a non resident last year?
The home is not an investment propery. We are renovating and it will become our primary home in 2010.

Are there any other deductions I should be looking at for this second home?

You can deduct the mortgage interest on a second home on your federal return - is that what you mean? I see no reason to file a SC return, as it seems it was not your resident state in 2009 nor did you have any SC source of income.