If you only want a handful, look for forums with that PR and start making posts. There are also some directories that allow free submission of links with/without a backlink.
The simple way is to identify do-follow blogs, then post relevant comments on any article in that blog. Even you can find few of the do-follow forums and add your link as a signature in those forums. You can get details in this blog by searching for do-follow forum and blog list.
You can find blogs with that widget (top 10 commentators) that is not nofollow and make some relevant comments on it!
All ways are true, but they are not easy. If you choose submit way, you have to spend so much, so much time.
I know a few ways: 1) if you have a blog, there's a great topsite blog competition thing, that has dofollow links, and some pr5 pages. The first link listed on this page: Free Backlinks for Everyone With Blogs 2) Use this Dofollow Blogs Search Engine and search for sites.... some will have pr3+ for you.
Can you tell me which article submission? Most article submission would post your article in new web pages which mean those pages are not indexed yet by Google.
Try using some of those images you have on your site: www.AddAnImage.com Post as many times as you like as long as each image is unique. It's free too!
Try to find do follow blogs and write meaningful comments in that blogs and you will get back links form that blogs , also bookmark your site or blog urls to all top bookmarking sites by that you will get good serps in search engines.
Answer questions on Yahoo answers with your link. I can do it for $0.10 a post, or you can do it yourself.
That's like finding a needle in a haystack. To do this, you would need professional automation tools. Bompa
Actually, it's quite easy to find high pagerank dofollow blogs - I've written about how I do it on my blog, at least. Check it out.