Rebates
Here is a list of local energy providers with links to the rebates they provide for energy efficiency:
http://www.alliantenergy.com/SaveEnergyAndMoney/Rebates/index.htm
http://www.blackhillsenergy.com/services/programs/homes-heateff-ia.php
http://www.heartlandpower.com/content/rebates
http://www.lennox.com/promotions/rebates.asp
http://www.prairieenergy.coop/aspx/General/ClientPage.aspx?PageID=604&n=664&b=2