Promoting your artwork online can be a task and a half, but it pays to know all the methods that you can utilize to promote and get the word out about your art, the online world is becoming vast and full of mini to large networks of artistic and creative types, so in the beginning, you will definitely want a blog or a website to showcase your creative skill in the form of an online portfolio.
A blog is a very simple and popular way of organzing all of your art into an online portfolio and a blog is very search engine friendly too, meaning that your blog can be found for certain search terms that your blog could start to rank for, for example if your art is fantasy based, you could organize all of your posts within your categories on your blog into keyword titled blog posts, this makes each individual blog post searchable, but it does depend on you sticking with blogging quite regular.
Free blogs like Blogger and Wordpress are ideal to start out and then within the first month you get a good domain name that will point to your blog posts and a good domain name is one that is a keyword related search term ideally and you can also pick up some free blog templates to make your blog look attractive and professional, to start off with that's all you need, because you will be supplying the content and your artwork and also it's best if you write about personal insights into your artwork, like how you created it and what inspired you.
Blogs work on many levels and they help give an insight into the artist and your work and you can quickly build up a following quite quickly if you are commited to blogging and you can dominate a niche if you provide value and show that you are approachable and enthusiastic about your subject.
Many artists opt for a static website in which you add the content on a number of static web pages, like a gallery page, a sketchbook page and about me page and a buy artwork page to name a few examples of pages. The content rarely changes except for updates that you may do to the site, but the smart artist will also have a blog that links to the static website, so that regularly updated blog posts feed updates to the site and also help rank your site in the search engines with every new blog posts that you create.
Search engines seem to like an updated website that updates often, as it feeds more content for it to index, so that the content itself can be found.
Along the way though websites need a little help and so do blogs actually, and there are ways to try and build more traffic to your artists website through social networks and building backlinks elsewhere.
Social network promotions
Sites like Facebook, Myspace and Twitter to name a few are ideal examples of website promotional tools, because you can build up separate networks on each site to aid your websites traffic, but don't rely on it too much at first until you build up your networks there, think of social networks as little outposts that you can place backlinks to, whether they are dofollow or nofollow, it doesn't matter, because you choose who to be friends and followers with and usually you choose the ones that are interested in your subject or topic, so that they maybe more likely to look at and read your website or blog.
Article marketing is a great way that requires dedication to do as you have to write related articles on your topic that you know about that will relate to your website/blogs keywords so that they will be linked together and readers of the articles will be able to find your website, I've started article marketing about 3 years ago and it really does work, although it does require a focus and dedication to follow through with it.
If there are other blogs in your niche or interest area it is wise to network with them and comment on their blogs now and then in a genuine way of course, if someone posts an article that you like you could tweet it or share it anywhere you want or you could link a blog post or website link to one of your websites or within a blog post if it's relevant to the topic at hand, I've done this often, because I find other artists work interesting and so I show my appreciation of it by linking to it or sharing the links around the net.
Social bookmark promotions
There are sites out there that you can create short bookmarks that will help to build backlinks to your web content, again these may be a mix of dofollow and nofollow (by the way dofollow is when the search engines index your links and nofollow is when they don't!), but it is worth doing bit by bit to create a natural linking strategy, ie: a few backlinks a day will be enough.
Delicious, Shetoldme, Redgage, Google Reader are examples of bookmark sites, but be aware that some may have banned some sites from leaving bookmarks on them due to excessive spamming and backlinking of the site, so just check out a bookmark site and find out for yourself what's acceptable and what's not.
A forum is a discussion area online that can be targeted towards a topic of interest or subject area and when established on the forum as a prolific contributor you can start to promote your website(s) in the form of a forum signature link that links to your website either with a direct http link or a keyword anchor text link usually done with BB code.
The benefits of participating in related forums are many and you can reach targeted people who might be interested in your blog or website, the key is to be genuine and helpful in the forums and answer questions as well as ask them, get to now other forum members and generally network with like minded individuals.
An about page
Most websites and blogs should have an about page, which explains why the website or blog exists and the reasons why people will find the site valuable it is very useful to use this page to link to all your other networks, so that people can connect with you at these other sites online, sites like Twitter and Facebook and any other sites that you create content, such as a YouTube channel or article directories if you write relevant articles that relate to your site.
An About page is a very important page, because it can usually describe what the site is about in the first paragraph alone, so make time to create one and direct people to it as well as the domain name of your site.