here's just some general landing page tips i picked up over time. i don't really have any split-test statistics to back them up, but in general they seem to be working pretty well.
use specific numbers as much as possible.
however, saying "you can make $10,561.73" makes no sense whatsoever. it works much better if you say "i made $10,561.73, and here's how i did it".
emphasize benefits (what it can do for them) rather than features (facts & figures)
put multiple [order now] buttons on your sales page if it's very long. like one every 3-4 pages.
use hand-drawn red arrows to direct attention towards important stuff (like order buttons and opt-in boxes)
include plenty of screenshots of actual promised results
include a picture of the product itself
use javascript to pop-up a message box when they try to close the page, offering them a discounted version of the product
simple graphics work better than fancy graphics
use a sans-serif font
use bold, underline, italic, red text, highlighting, larger font sizes, checkmarks, capitalization, exclamation points, and hand-drawn circles to direct attention where appropriate
include pictures with your testimonials
include a video
write a high price, then cross it out and put a lower price next to it
say there are only x number of copies remaining, or x number of hours remaining for this price, and put a timer on the page
if the order form's on a different website, put a screenshot of what it will look like after they click the order link so they don't think they're getting phished.
heh that's all i can think of for now
