• What kind of audience will be viewing my ad? - Some sites say they can "blast" your ad to 500,000 e-mail addresses for $50. Sounds like a great deal. Usually, though, your ads will be sent to people who are not interested, invalid e-mail addresses and so on. Send an e-mail to the site you're getting the advertising from and ask them for some testimonials from clients who have used the service, and reach some conclusions about the worthiness of the site.
  
  
• Pay Per Click Search Engines - Before you pay for services from a pay per click search engine, ask around about their reputation. A lot of these search engines recieve fraudelent clicks. It may seem like you're getting a lot of traffic, but make sure these clicks are translating into sales. Also many of these engines receive very little traffic. If you've signed up with an engine that you've never heard of, see if they have a free trial account you can sign up for so you can test them out before you spend your advertising dollars on them.
  
  
• 1,000 search engines - I've also seen some websites that will submit you to 1,000 search engines. Their may be 1,000 search engines, but only about 20 to 30 major search engines will yield you any traffic. Any worthwhile search engine company will ask at least $200 a month to promote your site, so watch out for sites that can't deliver the goods. Again, ask for testimonials.
  
  
• Newsletter advertising - Before you place an ad in someones newsletter, ask the following. How many subscribers does the newsletter have? What will my advertisment look like? Is the newsletter sometihng I want my company associated with?

Asking questions of the company is the most important thing you can do to weed out bad advertising. Remember you should get results for your hard earned money. Stick with legimate companies with a good reputation and you'll see the results you deserve.