Small trade oriented businesses can use 2 ways to maximize their presence on the internet:

1. Target the right keyword phrases. Starting with the keyword phrase you will reach your targeted market. For example: “auto mechanic”. Then target the metro / local area of business. “auto mechanic in Seattle”, etc.

2. Target using geographical tools. Google Adwords can be used to isolate geographical areas. You can specify specific longitude & latitude boundaries. So you could target a few blocks or a whole city depending on your goals.

The other strategy is to use the keyword phrase & then control the target by using the geographical tools in Adwords. This lets you reach a larger audience. but limits the exposure to a certain geography.

For further reading:

How to Get Your Business Started With an SEO Strategy

and if you have questions post them in the forums at My Solution Spot.