The best thing you can do for your friend is buy him a book. The book is called (no insult intended) The Complete Idiot’s Guide to Getting Out of Debt and is written by Ken Clark, CFP. Mr. Clark is a Certified Financial Planner and has many years experience working with people to get them out of debt. He also writes books on the subject (obviously), conducts seminars and gives presentations to employees of Fortune 500 companies all about getting out of debt, dealing with collection agencies, increasing and improving credit scores, and many other subjects of interest to debtors.
This is the best book I’ve read on the subject and includes an appendix of sample letters and other resources helpful to anyone who is dealing with debt of any kind and to any extent. This book would help your friend immensely. It is published by Alpha Books (2009 edition).