My uncle came into possession of the lesser half of an extremely rich, recently deceased art collector, and he wants me to help him sell it. I have no idea where to start. Some of the pieces I belive will sell for $500-1000, but I doubt any will go for more than that. Where in the world do I start? Should I get them appraised? Is ebay or craigslist a good place to sell fine art? Should I look into some of the famous auction houses, or would they only deal with more expensive pieces? Any advice would help.
Maybe you should put the two halves of the collector back together, out of respect for the deceased 
Call a local auction house such as http://www.dallasauctiongallery.com/ and explain the situation. They should be able to give you an idea over the phone and an informal appraisal and some selling advice if you show them the stuff in person.
First have an appraiser come out to identify anything of serious value, then set those pieces aside for higher auction or museum donation.
The rest, you certainly could sell it on ebay, although knowing something about the work (like the artist’s name and the media) will get you a better price, and then you will find yourself packaging a lot of art for shipment. That means bubblewrap, lots of cardboard, roll after roll of tape, styrofoam corners, etc.
You could donate the more nondescript pieces to an old folks’ home or hospital or veteran’s facility or some such. Believe me those places pounce on that stuff.
If you or someone you know needs something to do, I would certainly consider the route of renting a booth at your local flea market. Lots of eyes on the product, cash money, and the buyer will carry it away for you.
Got any sad clowns by Artanis?
Here’s a site that gives a history of art auction prices based on the artist’s name but it is subscription.
I’m so embarrassed. Clearly any sad clowns would be fakes. But if you have smiling farmers…
If the pieces have substantial value, I recommend Christie’s. If some of them are of more moderate value, I suggest Garth’s. Both institutions have been used by my museum in selling pieces and our experience with both of them has been stellar.
Contact them and tell them about your possessions. You may be able to do the peliminary work over e-mail (sending them photos and copies of documentation).