I have seen a couple of websites that offer linking to a PR4 site with an Alexa 2K, will this harm my PR or increase it, as I am currently PR1. How else do I increase the PR of my site. I am using anchor text to other pages within the site, using keywords.
If the site that is linking to you does not get penalized by google for selling you the link, then it will improve your page rank, however, you will need more than one pr4 backlinks to see an increase in your page rank.