So, how do you go about asking your visitors how they heard about you? Well, it's a fairly simple process: Basically you would use an autoresponder software program to produce an opt-in/squeeze-page. But before you produce your opt-in page and ask your visitors how they heard about you, you'll have to place this page in the right area of your website. Don't just ask the question on any old webpage, "...how did you hear about us"? This is doomed to fail if you do this in the wrong area of your website. It's useless to ask if your visitor really hasn't done anything. If you do you'll lose your traffic and you wouldn't get them back at that time.
You don't want to give your visitors too many options. So, the best time to offer an opt-in page is if your customer has made a purchase through your website. Don't forget; let them do one thing at a time. So after they have bought a product from you, send them an email and ask them: "Hey, I just wanted to know how you heard about me?" That way they would be more willing to respond since they've already purchased from you and they also see that you are interested in them.
This is the best way to gain feedback from your visitors. You'll find out exactly how they heard about you. There will be no guessing. Based on the feedback they provide you'll see where most of your traffic is coming from and make the necessary changes of where to put more or less of your time and money. It's a great way to leverage but also a great way to hear what your visitors are saying and a great way to offer them exactly what it is they want.