I do a lot of landing page designs for clients. Here are some successful pages I can show:

http://www.codedpreview.com/previews/68ce03ad/

http://www.codedpreview.com/previews/78709ad6/

http://www.codedpreview.com/previews/f2658514/

http://www.codedpreview.com/previews/96728435/

It's important to keep in mind that the most important thing about your landing page is that you send qualified leads to them. Some of the requests I get seem very silly or odd, but my clients are AdWords magicians and can get the right people to go to them and convert very well.

Many clients optimize the pages I deliver to bring in $500 a day, net. I've been in the affiliate marketing service industry for long enough to have some insights for anyone just starting with online marketing.

If you have any questions, feel free to reply and ask!