ClassifiedsBuy,Sell, or Swap for members only please. NO COMMERCIAL ADVERTISING - thanks...
And if you sell something like a boat through here - throw us a couple bucks for the site please :D
Katie, keep on an eye on craiglsist, your best bet will be through an individual owner. I just searched Boston CL for amps under $75 and a bunch came up.
People are always selling music equipment and you can get deals if you keep looking,