I need to obtain a letter about my rental history or a legitimate contact from a former landlord.

I moved to Chicago from Los Angeles area in September 2005. I lived at the Los Angeles residence from 7/2000 to 9/2005. The building was sold to a company called 800 Gold LTD in 2002. The onsite property manager rarely answered his phone, and later the phone number provided was out of service. Any interaction with the management company was done via mail and the property manager was instructed never to provide management company's phone number to the tenants.

Three weeks ago I contacted the County Tax Assessor's office to obtain a mailing address of the 800 Gold Ltd. I mailed a certified letter with a return receipt but a week later I still haven't received confirmation.

I found out that the address provided is actually a mail box. When I ran a Google search on the address it came up with another company name Landmark Realty & Property Management with a phone number that went to the real estate broker. I contacted the number and I am getting the run around trying to obtain this basic information. I have contacted LA Consumer Affairs, they require I send a letter to obtain contact information. I contacted the BBB and they have no reports on the company on file.

I am so frustrated what can I do to obtain this information.