I agree with Daff, first impressions are key. My biggest advertisement tool has been my truck, which is lettered, and I always make sure it is kept clean. In addition if I need to get any small part, supplies, or even just gas, I will take my rig with (making sure the tanks are empty). I can't tell you how many hundreds of business cards I went through, just simply filling up with gas, especially if it is a station that has diesel and local truckers are topping off before heading out.

Jason