When doing pay-per-click advertising (PPC), the most important aspect is your landing page. That's the place where you will either capture and keep your visitor's attention, or you will lose that potential customer forever.
Note that I did not say that making a sale is the most important aspect. That is true only when you are selling a single product (usually software or informational) that you can easitly describe and support with testimonials and well written copy (text).
Capturing the email address is the first and most important step in developing a relationship with your visitor, otherwise known as your "prospect." I think we should change the term to "targeted prospect" rather use that old, worn out "targeted visitor."
In the brick and mortar world, I teach my clients to treasure the phone call more than anything else done with the business website. For the Internet Marketer, I am beginning to lean toward a phone call instead of an email address. However, it is infinitely more difficult to get them to call you.
If you don't get the email address, they are gone forever. You won't have a chance to tell about your great products or ask them really important questions like what they thought about your website, why they didn't buy, what they need, what you can do for them.
It's like spending a lot of time and effort for absolutely nothing.
Keep in mind that the old "sign up for my newsletter" is not working very well. It just is not what they want in this world of thousands of email newsletters.
That is why you need an "opt-in" landing page. You have an opportunity to present an irresistable offer. How about a red hot report like "5 Sure Ways To Get the IRS To Audit Your Tax Form" during the tax season or in August "3 Reasons Why Your Child Can Fail Pre-School".
A good landing page can teach you a lot about what people are looking for. Using PPC (Pay Per Click -Google Adwords) you can do the testing you need to succeed.
The price to obtain your exciting free product is their email address. Capturing the email address is like finding a gold nugget in the cold stream.
Here are some examples of good landing pages. http://landingpageexamples.net/
Here is a nice long and very informative video to help you learn about landing pages.
Greg CrynsVisit Work At Home Profiles, an inexpensive membership website