It's going to be different for every individual site. The key is to get lots of inner-pages of lots of different sites that ARE COMPLETELY RELEVANT TO YOU to link to you. Relevance is key!! The only best way to get backlinks is to create great, useful content that people will naturally want to link to, aka "link bait". The backlinks will follow.
Please notify the Oxford English dictionary. "Lots" has been redefined to mean "two". :icon_rolleyes: But given cscgal's track record with this site, I'd lean toward her opinion of having great content and letting the backlinks handle themselves...even if it didn't seem otherwise obvious.
Create a signature and post on forums that are relevant to your niche. It will take time and effort but it can be a strategy which can work.
There's a caveat to this approach: make sure your posts are relevant and useful to the forum. Otherwise you'll either 1) be tagged as a spammer and banned quite quickly or 2) viewed by the community as a prat who's only interested in selfishly promoting his website to the detriment of the forum. Both are frowned upon. ;)
If you can't get links from very high PR sites, you can also do link building with lower PR ones that match the speciffic content niche you are in. In time, this proves helpful too. Also, make yourself known in social media, in order to receive votes that also help ranking your page.
I suggest you should search high pr social bookmarking and directory sites and post your link there as well as you should go for forum posting and blog commenting in those sites which are relevant to your site theme and social networking sites like facebook and twitter are those high pr sites which really gives your site high traffic.