I am facing to get a list of do follow forum and blog for my blog, my blog is contact lenses, some related blog are setting no follow, so is no point to leave a comment. Beside that what can I do? how about shopping forum or blog can built link to my blog ? if I build linked from unrelated blog or forum but high PR like PR 4 or 5, in the long run can help for serp? pls advice.
Tell you what - get into article submission - write articles and submit them to EZineArticles, Goarticles, ArticleBase, etc. Then write some things for web 2.0 props like Squidoo and Hubpages.
High pr 4-5 still affecting your pr, but not really suggested.. I have a site where without controlled are get backlinks from many unrelated category with mine, and the result is my site is not in correct category in alexa.. (not sure how this will affecting my serp..)