Contextual Adverstising
Contextual advertising (google adwords, yahoo publisher, microsoft adcenter, etc) enables anyone to get in front of someone searching for their service. It's quick easy and can be expensive if you don't know what you are doing.
My day job is a web developer and I'm actually certified in adwords so I am more than happy to field questions on it.
The top spot isn't always best for everyone. Many times in the DJ realm large multiops will get the top spot and if you try to go against them as a single op you aren't going to win, they'll keep upping the ante. However the top 5 spots through my experience have driven the most leads.
The key is making sure your ad and the content of your ad matches the content on the web page you are clicking through to. Google adjusted their algorithm a few months ago to place more emphasis matching the content of the ad to the content of the page behind it. It increases your ads quality score and enables you to place higher with spending less.
It's pretty complicated and if you dont know what you're doing you'll run through a ton of cash quick! Google does offer fantastic tutorials that goes through the entire program. If you have a week to kill go online and run through their video tutorials and you'll get a much much better grip on how to market cost effectively through them maximizing ROI.