Is there a listing of companies who do background searches. When a file is non-disclosed, there needs to be a contact list to make sure these records are not disclosed. Don't believe I have ever seen a listing. Hope someone can provide this listing.

I doubt that such a list exists as it would be vast and constantly changing.

If the file is marked as non-disclose then that should be the case, but it really depends on the level of background checking required.

Here is a link to a list of background search companies. Hope it helps: http://www.employmentverificationguide.com/firms.html

Almost any file or court action can be found, depending on how you want it done and the money you have to pay for it.
Most PI all do back ground searches. On top of that there are 1000's of internet search companies that do nothing but search public records and piece together info.