Hey there. I guess I'd consider myself a budget-minded part-time vintage audiophile, as much as I allow myself to be anyway.
Yes there is definitely a market for vintage stereo equipment. The value of the piece depends a lot on the condition, as well as the era it was made and of course how good of a piece it was to begin with.
Vinyl is of course in the middle of a major resurgence. Yes people definitely still play CDs, and you'd be amazed how much some people will pay for certain models of reel-to-reel and even cassette tape players in good condition. Rotted foam woofer surrounds can be replaced fairly easily and cheaply (obviously only worth it for a halfway decent set of speakers).
dcozad999, if you know someone with a Sansui 9090, those can be worth around $1k depending on condition. They're among the best 2-channel receivers ever made and highly sought after. I'd love to own a similar caliber Sansui at some point...when finances and space allow.
To the OP, the best way to find out the value of what you have is to open an account on audiokarma.org and ask in the "Dollars and Sense" section
http://audiokarma.org/forums/index.php?forums/dollars-and-sense.128/Searching ebay's sold listings is a decent option too. Just make sure you're looking at the Sold listings, not just stuff that's for sale. Lots of people list vintage stereo stuff for way more than it's really worth or ever actually sells for hoping that some naive deep-pocketed hipster will pony up twice what their receiver is worth without doing any research first.