George,
If you use the forum search function searching on "
inherited collection" you'll find alot of advice given to others who were in situations similar to yours.
This is a good place to buy and sell but you must first get your 50 quality posts, be a member for two weeks, and be a site supporter.
ebay, bidstart, delcampe, wensey are just a few of the other online venues that you can use. There are also an number of stamp dealers that buy collections.
Some potentially useful background information can be found at
http://stamps.org/Inherited-a-Collection Steve