Where can one find out which HOA is managing which property?

[Brendon K.]

I just want to find out if a property I'm looking at will have huge fees involved.

Screw HOAs.

[Jeff Keller]

Be careful about only looking at the HOA fee. The HOA for a local community could not get the homeowners to raise the fees to cover needed maintenance. Wood rotted for lack of paint leading to major expenses. Look for consistency and well kept homes.

In Silicon Valley, HOA documents are almost always part of the disclosure packet. If you can't get your hands on a disclosure packet, than as @Bob H. said, call the listing agent.