See Where do I enter qualified energy-saving improvements?
If you made energy efficient improvements to your home like energy-saving roofs, windows, skylights, and doors, you'll be able to claim the Nonbusiness Energy Property Credit for 10% of amounts paid for qualified energy efficiency improvements, up to a lifetime cap of $500 or fixed dollar amounts ranging from $50 to $300 for energy efficient property, including furnaces, boilers, biomass stoves, heat pumps, water heaters, central air conditioners, and circulating fans.
When you start the home energy efficient credits section, you will only see alternative energy (like solar and wind), this is part 1 of the form. Click Next or Continue at the bottom of the page and the next page will include heat pumps and other improvements.
To be eligible, it must be "An electric heat pump that achieves the highest efficiency tier established by the Consortium for Energy Efficiency (CEE) as in effect on January 1, 2009." You will have to check with the manufacturer or installer if you don't know this. The credit is 10% of the cost, including installation, up to a maximum of $300. There is also a $500 lifetime maximum on this credit, so if you have used it in the past, your eligibility now may be reduced.