After lots of hardwork in finding directories with good PR, I have compiled a collection of directories sorted by PR which i have published here: http://www.paiddirectories.info/pr5dirs.htm I hope my collection would be a good reference source for webmasters who are looking to buy links from high PR directories.
You can get one more good resource here : http://www.chattous.com/find-out-what-the-strongest-directories-are-from-aviva-source.html Aviva belongs to onlinedude (member here)
Try this list It is a compilation of 900 web directories with PR and some comment, that will let you know something about the directory. I hope this helps.