This is one of the mor difficult aspects of internet marketing and small businesses. Many others can spend more resrouces to get the word out at any given time. I have tried to approach it from a step-wise perspective. First step was to get the basic website out, without content you have nothing. A buddy of mine said to make sure that you do not make sure that you do not cludder ideas or muddy your message trying to stuff too much on each page. There are plenty of ways to make the search engines pick up your content in systematic ways.
Next, gather up your all of your suppliers or products that you normally use and make a simple page that links out to their official pages, that way your name or website will be linked to theirs. This will not in and of itself make a huge contribution, but if they look up this junk sucks, it will bring up your name. ;) As they say, any advertising where they spell your name correctly, is good advertising.
I am not sure if this next step was the best, but I found some of the low cost tshirt and mouse pad sites and through a bunch of products out there. People in general would not associate technical ideas with a tshirt. However, it gives you a different lane of approach to your content. Make sure that you fill out the description sections of each item and try to make sure your main url shows up in as many places as possible. These link backs help your search engine scores and increase the possibility that someone will click through to your site. Traffic, even bounce traffic is good. You never know whose little brother will see a t-shirt with a logo and pass it onto their brother the director of your next customer's organization.
Another simple and seemingly the most effective plan of attack. Use your open source community. They are mindless minions of habit. Ok, that is a bit harsh. However, Sourceforge, CodePlex and similar sites have huge mostly anonymous traffic, if you can publish any of your source code as a project and link back to your website you will get the word out to a large audience of people
with similar interests. I have found that techies run in circles and that they are inexoribly drawn to cool projects even if they are not in their fields of expertise. Likewise, if you use a product that has a user community, by all means post. Try to be as active as possible and keep posting your url in your signature. That link back thing is the cheapest and simplest advertising you can achieve.
If you can manage it, you may also put up single page advertising sites with kind of universal message information on any of the better trafficked free hosting sites. Google, Microsoft and all of the 500 pound apes have free sites. Free is good, at this point you are trading time for initial expense. So put up your message pages and cross-link them as best as you can without making them look like the original Yahoo. Different url's linking back help increase your score. If they get you 2% more hits every month then you are 2% ahead for copying and pasting an advertisement to a database somewhere. When it gets taken down in six months for lack of updates, oh well, it was free.
Tweets that get sucked into the ether by retweeters are good too. However, it is not as guaranteed a method because they are simple text messages and can carry less information than the free poster sites. By all means, spam the web with your message. With billions if not trillions of pages, make sure that you get your information out there in as many places as possible.
Blogging is my last idea, but it is not as effective. Just from a time perspective you have to keep putting into it and that makes it more expensive than just chucking out some posters. Posters are good because you can have a graphical message. Even back in the day...
Tamany Hall said they did not care what they wrote, their constituents could not read... They could UNDERSTAND pictures.