My ex-wife hired a lawyer and was able to convince Match.com that I
was a "head case" and as a result of that action my e-mails from
dating services and speed dating have been screened out. I was able to
find out that AOL ( MATCH.com) has an electronic memo basically
issuing a warning about me.  I live in Illinois. I am not interested
in a suit. I simply want to eliminate this infringement on my
liberties. I have a doctor that will testify against the allegations.
Besides AOL, she even approached COMCAST, work, credit cards, etc. In
essence every aspects of my life. She has made threats about attaching
letters to my electronic resume so that she can hamper my abilities to
get employment. This occurred three months ago. How long do I have to
correct the libel? What would it take and how much to eliminated it?

Get an attorney.  See if her actions amount to harassment.

Sorry this post is so late:
Libel, as an intentional tort, is governed by individual states'
statutes of limitations... these kind of torts usually range from 1 to
5 years, depending on the jurisdiction. Also note that libel, as an
intentional tort, provides the possibility for punitive damages. Thus,
an attorney may be willing to take the case on on a "contingency" fee
(meaning the attorney gets part of your award, rather than a set,
per-hour rate). There are interesting issues in your case, such as the
liability of not only your ex- but also any possible liability against
the companies you mentioned. Also, be sure to tell any attorney about
any concrete damages you may have experienced (any credit cards that
turned you down, times you were blocked from the dating sites but
still paid, etc.) You might also seek an injunction preventing your
ex- from doing these activities in the future.