We are trained to read from left to right with almost everything left justified.
In Yellow Pages ads that are more than a few words, justify the bulk of the copy to the left so that it is easier to read and follow. For an example, I'll show you two ads from the desktop publishing section of about.com.
They have a very nice collection of basic information on graphic design that I find quite useful.
For more information, check out http://desktoppub.about.com/
| Here's an ad that has everything centered. It's pretty difficult to read all of the information without getting a little buggy. |
|
Here's basically the same ad, except with the information aligned to the left.
Even though they make the classic error of using the business name as the headline, the ad is much more appealing to the eye and would perform better. |
 |
 |
 |