How many links do you need to get PR 6 or higher?

PR is meaningless except as a personal game or if you want to sell PR passing links back to other people in violation of Google recommendations. What really matters is a secret number that Google never discusses and that is where the art of SEO comes into play.

Anyways, you need PR6 or higher links to get to PR6. And it's a logarithmic scale so each step is much harder than the ones before.

This also is not really a forum to discuss SEO beyond basic SEO best practices, use http://forums.digitalpoint.com.

I think what you want is an SEO forum.

Here's an old school strategy: How about putting something of value at YouYap? Right now, it looks like a random list of spam-links.