how do i find out who has claims to my collection accounts

who ever reported it has to be listed on your credit reports. If they do not list who made the report, dispute it on grounds that there is insufficient information. IF they cant figure out who reported it and validate it, they have to delete it. IF they do validate , then you know who to contact to work out repayment with. IF the account in question is only being reported by the Original creditor, the collector Cant report it ( that would be duplicate reporting) and you would need to contact the original creditor and ask them who they referred your account to.

You could also contact the original creditor and either: (1) As them to recall the account and work out a repayment arrangement with you. If they wont do that, they should be able to tell you who they sent it to for collection and also provide you with their contact information.