you can try to create more back links to your site from different high page rank sites.there are different methods are available to create back links like article submission,blog commenting,forums posting etc.
Tips: 1) Quality Relevant Backlinks, 2) Quality unique fresh content, 3) Traffic, 4) No Coding Error, 5) No Broken Inner Links.
If your domain is new then to get good ranking from google take time. In the mean time give your site some quality backlink by exchanging link with your niche related website/blog. Definitely you will see good results.
Building backlinks is the way to get PR before but right now since Google has not updated its PR ranking system it would be hard to get some PR ranking for your site
Original relevant content and quality backlinks. Plus lots of patience waiting for Google to update PR.
You should try some methods: - Commenting on the blog/site have the same niche with yours. - Gest posting (this is the most difficult but very effective) - Submit your article to directoriest to get link back. - Buy link on high PR site. ect...
You should focus on getting good links from high PR blogs or forums, another great tip is to write good content for your website, google likes to see unique content and they will rank you better.
Paid links should have the attribute NoFollow which will not work towards Page Rank improvement. Google also penalizes paid links which has not been disclosed with the attribute NoFollow.
PR is not so important, unless if you want to sell links.. Important is your website ranking on search engine..