Whatever FSBO site you find, please look for RSS feeds options and subscribe them to your reader. Someone posted this information here somewhere (I could not find original posting) but now, I just go to my reader (in google) and basically search my subscriptions (FSBO sites) in one place with a benefit of having history as well for rents/sales.
I pull information from craiglist, kijiji, homespoint2, grapevine, usedottawa, usedgatineau, etc. in one place. I also post my own ads such "I buy houses cash" or "investor with cash".