These sites, and others like them, are aiming their brushes at both traditional art buyers and those who may never have hung anything on their walls besides a travel poster, but who have the discretionary income to lay out $3,000 (£1,834) for a work by an up-and-coming artist.
"The market for art extends from the college student who goes and buys a poster of a Matisse for $14, up to the collector who can buy an original for $95,000," said David Udow, vice president of Internet marketing at ArtStar.com, a division of ShowStar Online, an Internet content developer.
"I can't think of a person in North America who doesn't have something on their walls. We see the market as being all encompassing."
Buying fine art online might seem like a stretch, and indeed, most e-commerce analysts have paid little attention to the fledgling field. But one analyst who has, thinks it has great potential.
"So many consumers simply don't have access to the channels," said Mike May, an analyst at Jupiter Communications in New York. "This is one category where the Internet can incrementally grow the entire industry."
It hasn't happened yet, but the nascent business has scored some early wins.
At Guild.com -- launched by art sourcebook publisher The Guild -- one customer placed an order for 13 paintings and one photograph, worth $53,000 (Guild.com's average order: $425). The site won't give sales figures, but said orders in December were 2 1/2 times higher than in September.
In December, ArtStar.com auctioned off portions of the Chapman S. Root collection of Coca-Cola memorabilia and general Americana. In the first phase of the auction, which comprised 600 lots, roughly half were sold, bringing in nearly $100,000.
While it may seem that selling art online would be inherently more difficult than selling it in person -- after all, you don't get to see the work in person -- these sites argue that the Internet is a perfect fit for consumers who may be uncomfortable at galleries.
"A lot of those people are individuals who have the disposable income, but they don't necessarily have an art background and so may be intimated and puzzled by what's available to them," said Myrna Nickelson, CEO of NextMonet.com, which is funded by CMGI's @Ventures fund.
"That makes it more valuable to go online, because the demographics are obviously there. The market has always existed and been there, but they haven't been served adequately by the traditional way of doing things."
Making newcomers to art comfortable buying online is the reason many of the new sites are focusing almost as heavily on education as on the art.
At ArtStar.com, for example, consumers can look up terms and techniques in a glossary, read stories about new museum exhibits, or research artists and periods through online articles.