go with social bookmarking / guest blogging / articles and directories.
Hi Mate..!
For your information, without OFF PAGE optimization you could attain high PR for your website by doing perfect ON PAGE optimization.
Better you go through with getting links from authority site like ( .edu, .gov) sites. Try to make profile building and getting link from authorized profiles. Document Sharing, Squidoo lens Submissions are one among the best link building techniques, that ever lets you to drop your PR.
Article submission, Social bookmarking is also helpful...
If you need quality backlinks then first you need to work on OnPage SEO.
Once it is done then starts off page like Social Bookmarking, Guest Blogging, Submitting Infographics in sites like www.infographicsonline.net. You will get quality backlinks from this work.
Directory submissions are also helpful but try to submit in best quality links because there are many spams.
You can hire trusted SEO service for it to ease you with the off page SEO campaign. On the other hand (on page), make sure you provide high quality (not just informative but valuable) contents. This kind of contents will make others like to make link to yours. I've done it and it helped me a lot.
You can submit some articles and press releases to high Pagrank websites. It will work.
r also suggest other way to achieve high page rank for a website
