How blogs can help to get us good ratings for my site in SE's....

Cheers,
Rajesh

Blogs would be only part of the current theme. The whole picture would have to present that the target site is an authoritative site.

Such a site would need all aspects of search engine marketing to compete.

Optimized content, blogs, published article content, directory listings, and an over all community building presence.

This is what the competition is doing. An SEO much consider all of these aspects to rank top 10.

If you thoroughly lay out these plans to a client, they will finance your efforts.