Ebay, gumtree, preloved, free ads or your local paper.
Value wise they are worth what someone will pay for them.
Search eBay for your items , ticking the 'show sold items' box and you will get an idea of what they sell for should you wish to advertise elsewhere.
Listing on an auction site with a low start price, they will sell for whatever someone is willing to pay for them. If they are quality items they will most likely achieve a reasonable (to you) price, without you having to know what they are 'worth'.