I myself run a batch file that searches any craigslist site within a 300 mile radius or so for whatever keyword I enter. It opens about 25 Firefox tabs full of (hopefully) Amiga stuff.
Generally just going to your main craigslist site and typing "amiga" in the search will search all the for sale areas, and will often search other geographically nearby craigslist sites if it doesn't find many results.
