when a provider is de-listed, is there a way to pull up the information showing why she was de-listed?  It would help if that info was available rather than the search coming up "No records were found".

Nope, no way to search out their information, or why it isn't there anymore.  It is also against the rules to post anything in the forums about them by name.

If you know the moniker(s) of their respective reviewers and do a "search by reviewer".

I submitted a review on a provider and it comes back a couple hours later as unapproved - Provider delisted??? I am the first one to do a review and I just saw her. How could she be delisted?

It aint too likely that any of us is the first one to see a provider.   If the provider is delisted, you can bet that prior posts have been made, and she has asked to be excluded...bye the bye, one of my favorite providers is delisted, so my long review rating her 9/9 was rejected...it is not a sign of a bad provider per se.