Joan Beringer's blog on licensing art is very helpful. This particular post is on what sort of business you need to have regarding licensing your art. In the recent past she has also blogged about details of registering work with the US Copyright Office, and lots of art business topics.
Sell Art Like the Galleries, from Art Business, is another good one.
Do you have a studio or space in your home where you invite potential buyers?
After our last move, I was able to claim a room for a studio for the first time! And, for the first time in quite awhile, we had room to have people over, a place to sit, wall space to hang a lot of art, etc, so I'm making use of that. I decided to keep all the art I collect from other artists in my office. If a guest does see that area, I can easily say, "This is where I keep the art I collect." Then they won't have to ask, and I won't have to explain, every single piece in there separately.