a few more ideas
If you're looking for local gigs, go to local meetings for various groups where people who might be in the market for your services tend to show up -- but only if you're able to get some value from the meetings other than marketing. For instance, if you're a programmer who happens to run a consultancy that does workflow process training for programmers, going to a Ruby Users Group meeting (for instance) to learn and meet people can potentially lead to people going back to their employers and talking about the need to get you into the office to train people -- especially if you give well-received presentations to the group from time to time. It's a bit like "blogging" face-to-face, reaching fewer people but doing so more forcefully and in a way that is much more locally valuable. When you give a presentation, make sure you post your presentation slides somewhere either on your consultancy website (maybe in that company blog) or where links back to the consultancy website reside.
If you are on a community mailing list of some kind -- perhaps including something like the freebsd-questions list -- and you are an active, polite, helpful participant in discussion there, including a link to your consultancy website with a company slogan or something along those lines in your email signature block can help draw potential clients to you. Just make sure your email signature block is still not more than 80 characters wide and four lines deep, in total; it's just good online etiquette.
Regarding the suggestion of contributing to open source software projects, there's also the option of simply writing some open source software from scratch and maintaining the project, or picking up maintenance of effectively abandoned open source projects that people still use (or might still use if they were brought up to date). This is particularly helpful if the software is something of special interests to that selection of people and businesses who fit into your preferred client demographic.
