If you don't feel like ebaying it Beauty you can do one of two things:
Call several estate sale companies and ask them how they run estate sales. Most will come in and go through the stuff for you. They categorize it, price it at decent prices, do the advertising, etc. all for a percentage. Most companies who do this are also antique dealers, so be prepared for them to possibly offer you money outright for anything of major value (of course, probably about 50% of what it's really worth). I don't know how they handle them in Mississippi, but up here the sale is usually in the house. They'll try to categorize stuff room by room - i.e. dishes in the kitchen, one bedroom may be used for linens, one bedroom may be used for books, etc. etc.
You can also call an auction house. You will need to rebox the things into categories - dishes, silverware, books, etc. - and either drop it off or have them pick it up. Get a receipt for everything. Every time they have an auction, they will put some of your stuff out and anything that sells, they keep a percentage and mail you a check. It usually takes 4-6 weeks to get a check after the auction happens.
Either way, make sure you clearly understand their terms and conditions for the sale. And also remember that commission percentages ARE negotiable.
