Look for any venue which is willing to host wedding receptions and the like, but which doesn't serve alcohol on site. That means that they've probably got the insurance policy which allows people to bring alcohol on site, but no problems with stupid laws about bringing alcohol into a bar.
Some private clubs, like the Elks or Moose Lodge, might have rooms you can rent which aren't technically part of the members bar. Some churches might also have rooms available.
Once you've got a location you like, do what it takes to get in good with them. Pack out your trash. Clean up your messes. Don't let your members get obnoxious. Do them favors. Try to throw some trade their way.