I have read Dave Ramsey's book Total Money Makeover before and I really enjoyed it. I liked the way he broke getting out of debt down into small easy to achieve steps- his baby steps. And, I was won over by the idea of an emergency fund! If I had known about that when first starting out things would have gone so much differently for us.
Thankfully, we have been trying to follow these principles and we are slowly getting out of debt. However, we have been in a financial strain before- repo on a vehicle, debt collectors calling, etc. And, I never knew how to handle them!
In his book Financial Peace Revisited, Dave goes into detail on how you deal with debt collectors. He even has some sample letters for you to copy and mail.
He's added in sections on your credit report and why it's important to check it regularly, as well as how you handle disputing an error.
There's also other really nice additions like how to opt out of those mailed prescreened offers.
If you have to choose between his two books, this is the one I recommend you choosing!