I think directory submission is not effective as before.In addition to directory submission you can try link building methods like social bookmarking,article submission and forum posting.

Directory Submission is really helpful because from that you will get permanent "one way link".

Directory Submission is still affective but main thing is to submit your website in high pr directories.

You have to use a broad selection of tools to get backlinks, this is what Google is looking for, so you have to look at article submission, blog commenting on commentluv sites (leading your anchor text as user name), directory submissions (not as effective as before), create hub pages, squidoo lenses and also post unique content on blogger etc.

The wider the spread of sources your backlinks come from the better.

Try using different methods for increasing PR like articles submission, squidoo, forums, twitter etc. Directory submission is useful but not using it as a single tool.

First mistake is that youi think PR is important wich is not is just a number RANKINGS are all that mather and PR and RANKINGS have like no connexion (also PR updates once 3-4 months)

Second big mistake4 is thinking there is any magical link building method like articles prs etc etc ... it's just one of 10-15 link building methods ...

Dirs 2-4k submissions is a good start of getting one way links with desired anchor texts but you need much much work to reach decent rankings

Thanks Everyone for providing valuable information.
If anyone have high PR directory list so please provide me.

Thanks in advance