There was a thread not so long ago that had some great ideas about bike procurement such as lawn signs and flyers.

I've tried them and they work.

I've tried leaving notes and approaching folks in person.

My best source of bikes in Germany came from a casual conversation at church!

They all work to some degree.

The best thing to remember though is a modified version of buy low/sell high.

I use buy low/sell fair.

Keeps me up to my waist in fun projects.