Sorry if this isn't at all what you are asking, but I'm going to assume you're talking about placement of the opt-in form. I usually just put it at the end of a very short sales pitch, in the main body content of my website. However, that's when I'm using sites built exclusively for list building. When I do, however, make a content website, and I want people to sign up for my newsletter, I put it in a Google friendly pop-up. There's a program that will create this for you, but I can't for the life of me remember what it was... does anyone else remember? Check out the following website to see what it looks like: http://www.ultimatewealthpackage.com They have un-blockable, friendly pop-ups that recommend people sign up for their list. I would also recommend putting it somewhere on your site aswell, be it at the bottom or in a side bar. If you've got any other questions, I'll do my best to answer them
Opt in is absolutely the way to go and do it quick if this is based on some one time news event u came across. If people wander off of your unfinished site and never come back, you will have lost thousands of email possibilities.
A jeffC, I think you should write an e-book and sell it. If you know how to get that kind of traffic, you must write and sell it to to make money. I would definitely pay for a book like this.
I don't agree with Onera. I think you should keep focused on your niche, and keep as far away from the IM niche as you can for now. You need to build up a lot of experience before you can hope to be successful in the IM niche, and as such I would just work on trying to convert your traffic, instead of working on teaching others how to get similar traffic. Also, one traffic strategy into an e-book will only sell for somewhere under 10$, so it would hardly be worth the effort. The only reason for selling a book like that would be to use it to collect e-mail addresses for a second list (7 dollar script, anyone?).
You can have a little email sign up script there asking if they want to be informed when the site goes live.
What would be best, a sign up on the side of the content, or a pop-up page asking for users to sign up?