daveramsey.com is a good source of information. See for example http://www.daveramsey.com/radio/highlights/?urlVars=2010/7/1...
A few particular points -
Don't use a debt consolidation company, they're a rip off.
Get a copy of your credit report so you know who has your debt and for how much.
Deal with your debts one at a time -- smallest to largest.
When you have some money, call the first debt collection company (the one with the smallest debt). Negotiate a settlement in full. Don't pay them anything until they agree in writing that your payment settles the debt in full. (Email counts for in writing). Do not send them a personal or business check that has your checking account number on it and don't give them electronic access to your checking account -- they will clean it out. Send them a cashiers check for the settlement amount instead.
Repeat for each debt.