I've been reading (mostly Mr. Yet's) answers re. Fair Debt Collections, and I've read the Act itself. I don't speak legalese, though. Is there any law that requires a collections agency to justify charging interest at a rate higher than the legal limit? Does obtaining a default judgement without delivering a summons constitute a violation of the fdcpa? Does anybody know a good, affordable attorney in the Metro Detroit area?
I also suspect that creditors have been sharing information about me, as I've had 3 come after me within one month, 2 of which have claims that are completely invalid because they're for debts that I paid off years ago. Does anybody know if or how I can find out if they're talking?

Does obtaining a default judgment without delivering a summons constitute a violation of the fdcpa- it violates the law.

They have probably sold your information to anyone willing to buy it. I don't know what the laws are in your state on how they have to document the summons process. This is where I would look for answers. You can motion the court to vacate the judgment if you were not properly served. Plaintiff has to prove they served you properly or the judge will likely agree to your motion, then your off the hook. You can then inturn sue the jerks. I'd seek a good civil attorney, look through the web or ask friend you know.

Try this. Might be helpful

Fair Debt Collection Practices Act - You can Fight Back!

Interest is regulated by law, there are laws against usury. A summons service is also regulated by law. If they claim a s ummons was served fraudulently, that's illegal, but that's hard to prove.