This is a simple trick to find PR4 pages. One of my friend shared this trick with me. It a way to get links from Digg. At first go to digg.com. Then pages that are older than 365 days. There you will get lots of high page rank pages Digg. Old pages and some new pages has high page rank on Google. Find your post related pages. Then check page ranks using online page rank checker. Now make a comment and post your URL on those pages . Your link is now on a high page rank page for free. Search around and keep looking.. you will find some pages that are really really high page rank such as pr8, Pr7. Here are the steps to get PR4 Backlinks from digg with Example link:
1. Go to digg.com. If you have a Digg account login to Digg or Signup for new account from Digg.
2. Find some old pages from Digg. Go to pages 365 days older or older than that.
3. Find your post related pages from older pages. Then check page ranks using online page rank checker.
4. Post comment on high page rank pages with your link in comment.
One Example digg link: http://digg.com/programming/A_Better_Digg_This_Button