2012 Energy Tax Credit Information may be found at www.energystar.gov/taxcredits

Federal Tax Incentives for energy saving technology
http://www.energytaxincentives.org/consumers/
http://www.energytaxincentives.org/builders/
http://www.energytaxincentives.org/business/

Update as of 2/13/12:

Several tax incentives expired at the end of 2011. These can be used for investments placed in service in 2011, but do not apply to investments in 2012, unless Congress votes in the next few weeks to extend them. Incentives that expired on 12/31/11 include:
Residential insulation, windows, heating and cooling systems and water heaters
New homes that use half the energy of a home building to model codes
High-efficiency refrigerators, clothes washers and dishwashersFive incentives remain in place:
New and retrofitted commercial buildings that use half the energy of a building built to model codes
Combined heat and power systems
On-site renewable energy systems including ground-source heat pumps
The first is currently scheduled to extend until 12/31/13, the other two until 12/31/16.
 
 
 
Montana State Tax Credits and Rebates
 
Get money back on programmable thermostats, insulation, lighting, and more.
http://www.northwesternenergy.com/display.aspx?item=102&;page=rebates_home_mt