There are currently 2 different tax credits available to certain buyers in the US. To be eligible for either, you must have an accepted offer on a house by April 30, 2010, and close by June 30, 2010.
The first is an $8,000.00 credit for first-time homebuyers, defined as not having owned a house in the last 3 years.
The second is a $6,500.00 credit for repeat buyers, defined as having owned a house for 5 out of the last 8 years. To be eligible, the home must be a primary residence, not a rental, or vacation property. There are also income and home price limitations. To find out if you are eligible, consult your tax specialist.

The site I’ve found with the most information, and the easiest to decipher is: www.federalhousingtaxcredit.com Always consult your tax specialist to make sure you qualify.