It can depend on what program you're going for.
Some have income vs. family member guidelines (Neighborhood Stabilization Programs), low income ratio's, standard/conventional guidelines, etc. Not always the 3 year rule unless your going for tax credits.
My best advice would be to go under "Find a Pro" and discuss your situation with a local Realtor in your area. They would be able to guide you through the exciting adventure of being a first time home buyer!