Being that I worked in a RadioShack within the past year, I can assure you that they do in fact carry cellular inline recorders and regular landline inline recorders, along with induction coil mics. I've touched them with my hands physically, putting them onto the shelf. Don't tell me they don't fucking have them, because they do.
HOLY SHIT PROOF:
http://www.radioshack.com/product/index.jsp?productId=2062697http://www.radioshack.com/product/index.jsp?productId=2141764and here's a picture of me with an inline recorder attached to my head while tripping on LSD from 2006:
You put that suction cup part on the phone receiver, not your head.
Once you hook up your inline recorder ACCORDING TO MANUFACTURER'S INSTRUCTIONS and have it all hooked into your computer's microphone jack, you'll be able to capture both sides of the conversation with either Cool Edit Pro 2 or Audacity. Either one works fine, I assure you. Once you've captured the audio, all you have to do is save it to an .mp3 or whatever format you chose. Personally, I use Cool Edit Pro, and I have for years.
And as for talking trade with, I could have swore we did that on the entire first page. Sounds like you're not looking hard enough in the correct places. Alright fine, after all that, you happy? Maybe you should put this one in your 'shattered dreams' box, eh?