Online advertising is the best, and most effective, way to advertise your company, services and/or products. However, if you're not careful, it can be one of the most expensive ways to advertise.
The single-most effective and inexpensive way to market your business is to have an optimized website! The cost of a website vs. printed and promotional materials is minimal if you can effectively target your key audience/market with your website.
If you have a website, but aren't getting any results, you should check to see if your website is optimized for the search engines. If it is, it should be bringing you targeted people who are looking specifically for the products and services that you sell. If it is not optimized, you will want to read more about Optimizing your Website for the Search Engines.