You have a couple of options, check out the Bluebook feature here on Audiogon, and/or search completed auctions on Ebay. These data points should give you a good idea what your stuff is worth. Welcome back!
Laugh but give me a clue
I hate dickering over prices. I sold all my audio equipment 2 years ago and all I had left after paying for my Daughter's school was about 2K. So I bought a reciever and a pair of Cambridge Soundworks Newton T300. They cost $1600 brand new and they are Perfect in appearance. Now I'm able to get back into a hobby I loved so much. I know I can't get much for these but what are they worth? I don't want to look like an ass asking 50% If these don't deserve it. I'm looking to buy a set of speakers that is more for music alone than HT. Thanks!