Keep Our Homes Act of 2008 - Amends the Internal Revenue Code to allow: (1) a tax deduction through 2012 for mortgage counseling costs; (2) a tax deduction through 2009 for amounts, up to $5,000, of mortgage indebtedness in excess of the assessed value of a principal residence; (3) a one-time tax credit for a percentage of the purchase price of a principal residence; (4) nonitemizing taxpayers a tax deduction in 2008 or 2009 for real property taxes; and (5) an exclusion from gross income for unemployment compensation received in 2008 or 2009.