You can always use various tracking tools on your ads to see if your ad gets read or clicked, but how do you know that the tool you are using to promote your business is actually working? Well, you could also use tracking for that, but how do you know if it´s your bad ad´s fault or if it´s the bad tool´s fault that your ad is not getting read / clicked? Well, this is getting sort of complicated. My point is this, you can use tracking tools for almost anything and you can probably use them to find out if the program / tool you are using to promote your site is working as well, but there is another way too.
First, you can use only programs and methods that you know will work if your ad is good. That would be something like Google AdWords (expensive, but it works). Second, you could use a program that someone you trust recommends to you. Or third, this is my point today, you can join Traffic Testers and read an unbiased review on all sorts of marketing tools.
I trust that they are unbiased. I have only subscribed to their newsletter, so I really don´t know how good their site and opinion is. They state on their site that their archive is full of tests, more than 150 tested traffic and advertising sources.