If you want to pinpoint a particular area, the best way is the Haines Directory.

Steven Maduro - Here's a directory of online rent payment tools.

I'd also jump on the Article directory and start reading.Once you have a good idea of what you're interested in (landlording, wholesaling, etc), dive into those forums.Condos can be good investments, as can any other property type.

Ashley, the hard money directory here on BP is under the resources tab.

Might check the past City Directory, a publication that has cross references by names, addresses and phone numbers.Might check with business licenses office, they may have records by address.Check the Assessors office for business personal property records.Look in the property records for filed notices of lease agreements.I'd probably just ask neighboring property owners who they remember being in there.Old timers usually know who use to be there.

Jake, the first thing I would do is post my company name in the Private Lender directory of Bigger Pockets.

I'm happy to announce the introduction of:BiggerPockets.com Property Directory - http://www.biggerpockets.com/properties/You can now list your FSBOs, listings, etc for FREE!

Is it true that lenders look for your business to be listed in all major directories before they consider you for financing?

The FDIC institution directory lists 7,607 active banks.

I can't share any experiences with other auction companies, but we've got a directory of them on the left of the forums:Land & Property Auctions