Look for Early Editions of Encyclopaedia BritannicaThe basic guideline is that the 1st up until the 8th Editions have great collector values, defined by condition. The 9th and 10th Editions are so numerous that they are of small value. Anything after 1928 is basically worthless.
Selling Old EncyclopediasFor over a year I have tried selling an encyclopedia set that is in pristine condition on Craigslist. I have even seen ads where people are giving away their encyclopedias for FREE. Due to the internet there is nothing that you can't find that isn't in the encyclopedia except the photos.
