I need Some SEO expert for my web site promotion and Ranking within short period . Please advise me how to get SEO expert for my project.

Hi you can search for some good seo experts on the internet in either freelancing or post in job portals to get a full time working completely for your website.

Search online and there you can get a long list of SEO experts and just try to interact with each one of them before handlng them projects. try to avoid companies who do not know how to handle Panda and penguin google updates.

There are many Guru's online so pay attention where you knock!
Before starting any contract inform yourself about some basic stuff on what is SEO, after check reviews of the SEO company that you decide to work with.

freelancer.com is usually pretty effective for somebody looking for a freelance professional and prices are usually relatively low - no garauntees on the work though.