You should be able to report it in the Sale of Main Home category and it should walk you through things. But read the screens VERY carefully, as they can be confusing.
One screen will say something like did you use this as a Home Office, and you need to say YES. That is where you enter the depreciation that you took when it was a rental. That amount of depreciation will be taxable now.
Although the gain from the sale of your main home can be "excluded" (no tax), the laws changed in 2008, so in your situation your capital gains will be prorated. The prorated period when it was a rental from 2008-2010 will be taxable. But again, if you read the screens very carefully, it should walk you through things.
