Indeed, some people like to provide "white books" in exchange of your email address. The goal is to get contact information to generate leads. But as a matter of fact, you will have very poor return rates if you base your strategy on it. Indeed, as David says, email information is personal and has a value. And most of the time people either doubts about the value of the content you want to provide in exchange of the email, but also knows it is not worth it.
The idea is to have a facial value of the content you are going to provide is higher than the email address value.
Here is my thoughts:
1/ Have free interesting content
The first thing is to create traffic on the page. Therefore you need to provide interesting news and information on your blog/website. You need to show your know how, to give tips that shows also you are eager to help the reader.
2/ Create a high value package
You need to understand what would be worth your reader to contact you. Is it white pages? Is it a tool? Is it a check up? You need to figure it out.
3/ Find out the best way to establish the contact afterward
You need to think about a step further. How are you going to actually go beyond giving something out, but you sould think about how you could jump on the occasion to meet with the person, or proposing an extra service.
As I was working in the mortgage business, I have seen once the website of a mortgage broker that I always quote as an example. They had a very nice website, with a lot of information. But they were also proposing a special package, which was worth couple of hundreds dollars. This package was including some reports, tools to manage a mortgage, among other things. But also, if the person who downloaded the package was actually getting a mortgage with them, he could gets back his hundreds of dollars from the mortgage contract.
Very interesting as it was also hooking up the reader into the will to actually buys his house with them.
What do you think about it?