What was the reason of debt forgiveness?
Sale of your home? credit card? bankruptcy? others?
The amount of debt forgiven reportable on 1099-C - http://www.irs.gov/pub/irs-pdf/f1099c.pdf - generally is taxable, unless an insolvency exemption apply -- you should file a form 982 - to proof your insolvency - and might exclude all or part of canceled debt from taxable income.
Please see the IRS Publication 908 Bankruptcy Tax Guide - http://www.irs.gov/pub/irs-pdf/p908.pdf - with example of the form 982 on the last page.
Please do not be misled by the bankruptcy guide - you may be insolvent without filing for bankruptcy....
You need to fill a form 982 - to proof your insolvency - that would be sufficient to exclude canceled debt from taxable income.