Best place to start reading....
Introduction to Credit Repair (and a lot of the other threads in the beginner's section)
You start by opting out........and updating/deleting personal info.
You want to make sure and remove ANY and AS MUCH personal info as you can.
It will help when you dispute accts later on. The CRAs will cross check information with the CAs. The less info they have to cross check, the better.
The personal information on your CRs is not necessary at all. The ONLY things that need to be on there is a current address, your name (no variations if possible) and your SS#. No previous addys, no employment info, no phone numbers.... So you always want to try and get as many things as possible deleted.
You can do this by disputing all of your personal info by mail........OR if you want to do it quickly you can actually call them and it goes pretty quickly that way (that is really about the ONLY time I would advise calling a CRA though).
Now as for the rest of it........you need to look through your CRs and see if any of the information on there is incorrect. You basically need to "triage" your CRs. See which ones are out of SOL........start with the oldest ones first.
If you are unsure, once you have taken care of the first couple of steps, let us know what kind of debts they are.......or how they are reporting......then you can start to plan a form of attack.
HTH