I'm currently writing a Steampunk Adventure novel, and I'm hoping to build up an audience while I write. Basically, I'm wondering what you (a published writer) did to build your audience (if anything) before you began submitting your novel to agents, or before you began the self publishing process.
I started writing before making any attempt to attract an audience. I'm not sure how much of a readership it would be possible to attract without anything for them to read. A blog about the writing process is one way to connect with people as you write, but that's most likely going to attract would-be writers, and it's not clear that that would translate into book buyers, ultimately. You'd probably be better off putting the energy and time into the novel rather than marketing for a product that doesn't exist yet.
The first things I worked on were short stories. You might consider that route as a way of connecting with an audience, since the short stories you produce as you work on the novel can appear in a number of places before a reading audience, and each one potentially attracts some readers to your website, or blog, or however you choose to present yourself on-line, which means that when your novel does appear, there will be people who've heard of you and seen your work.
I think Paul is right. I have a webcomic and I'm writing novelettes and novellas to augment the world for my readers. I have sold some. In addition, I know one woman who has a fictional blog that is really telling a story. Pretty much a serial liek inthe radio days, but online. It's kind of cool.
I say build your world and they will come. :)
I started by keeping interested friends informed via Facebook, so that I had a small audience waiting when the book was finally produced. Then those friends, when they read the book and enjoyed it, spread the word to their own friends, so that word-of-mouth blossomed out into what turned out to be decent sales for an unknown indie.
Building an audience takes a while, but I think the most important thing is being social. You should have something for people to read, to get a 'feel' for your writing style. I wrote short stories and had them published on different markets, and now have links to them on my blog.