This sort of stuff. Local landscape, local historical interest. The .jpgs look positively lurid here, something's wrong in color management land. The favored size range is around 30 x 80 for the interior, 29 x 96 for the landscape. Best selling sizes are a little smaller, but not much. I have sold a few 40 x 120 pieces recently.
Anybody who lives around here recognizes the landscape, or has heard about the interior which appears in a lot of recent movies. Don't think for a second those frames will work wherever you are, but they are OK for a lot of the houses in the Southwest. I have slightly more generic and modern frames for offices and institutional buyers. But I don't do the stultified thin-black-frame thing at all.
Best advertising is by far contacts made from being in local art fairs. If there is an upscale art fair near you, make sure you get in. Also I get lots of sales from displaying in community centers, restaurants, and galleries...in about that order of success. Also got the interior shot into a museum show that's up now, that resulted in several sales in the last week. I sold a few at the opening, then a few more when I gave an "artist's talk" a week later. Also get sales from people seeing my work at my customers' locations, that's starting to reach critical mass now, yoohoo!
Media ads are essentially worthless, spend you money on making product. I've gotten a few interviews in local newspapers and art rags, for which I egregiously leveraged my former day job. Those interviews impressed other artists, but barely make a dent on public consciousness of my work. Bottom line...publicity and advertising take a back seat to having stuff on view in crowded public venues, that's where the action is. Bottom line #2...your images will sell a lot faster if you are around to pitch them. Artists can sell their work in person at about 4X the rate of a gallery salesperson. Never fail to attend an opening or any kind of public event where your art is present.