Let me go direct to the point. Let's start with some offline low budget marketing first.
Newspapers classified ads: make it small and direct, this will give you real sales calls no just ramdon advice seeking.
Fax ads: Send one page fax flyer to every local business on a monday (don't send it to your competition). You can use eFax to do this. Don't do this all the time just once a month with a service promotion and expiration date.
Grand Opening: Make invitations and hand them yourself to your city authorities (like the Mayor, Police, Fire department), and to local businesses with many people that can afford a computer (like Car Dealers, Lawyers, Hospitals, Nursing Homes, and more) don't go to factories. This can get you a lot of business and marketing exposure almost for nothing, because where the Mayor goes, the newspaper reporters will go, too.
Flyers: Put flyers on every neiborghood store or 24 hours stores (ask for permission from the owner or manager).
Start a small web site with your offers, rates, service list, and contact info. Simple is better...
Start a web blog where you can post computer tips (don't teach them how to fix a problem), just tell them how they can avoid computer problems. Also, you can talk about everyday stuff at the job, but don't talk about your offers or services, just put some links on the side bar to your web site pages...
Search Engines: own your web site content and Meta Tag add keywords like your town or city name and state. You don't want visits from California if you live in New York. Them submit your site at SubmitExpress.com
Well, hope this can help you. If you have a large budget you can put some half pages ads on newpapers about your grand openning. After that just keep record of your customers, and ask for referrals (always).
Luis Galarza, Business and Telecommunication Consultant