This thread topic has already been discussed here in this forum. Try using the search functions that would match your query as there are a lots of answers that has been provided to your question before.
you need links, but quite honestly PR is useless and Google doesn't even care about it so much anymore. I recommend working on SERPs and traffic instead of shooting for pagerank (unless your flipping sites)
Link to page with a higher page rank than your. If you have a ranking of 2, linking to a website with a rank of 6 may help to increase your ranking. Make sure your website is well balanced in all areas. Strong content with proper technical design may help increase your SEO page rank a good ideal.
will Google ever consider going open about such technologies as Pagerank? will there ever be such thing as Google Pagerank API?
in order to get a higher ranking you should keep your site updated, you must always have an interesting contents,then be patient to do the link building for your site,press release,classified ad posting,forum posting,social networking and social media networking can help you a lot to attain good impression.
Get dofollow links coming from top sites related to your niche. Basically, increasing the volume of backlinks will make the PR increase (depending on the quality of these backlinks of course.)
You can always buy domains that have valid PR and use those to build links back to the site you want to build up in PR. (Hint: look at my signature.)
Although PageRank may not be the only element Google considers in order to give websites some ranks, but by adding links to your website, especially from high PR pages like directories or homepages of websites, you can expect some PR boost in the coming updates.
Link buliding is the time consuming task, but the rewards are very satisfactory once the web page start receiving visitors from the big search engine. Every effort put into link building will be worth.
Well, we cant say about any exact time to get page rank because it's all depends on the search engine that how and when it will give a PR to your website, all we need is to follow the rules and regulations of the search engine so that we can get some good and relevant back links with a valuable PR whenever it updates its algorithm...