DISQUS

Hey Harish. Yes, Heather Soloman has great stuff on branding - I would recommend looking into her stuff. She even has a css reference chart to show you what css elements control what sections of a SharePoint page (I really like that chart).
My suggestion on getting started with branding in SharePoint is to start with just generally css branding. Try changing the css files around to see what you can do. After you do that maybe go into SharePoint designer and start changing the Master Page on a site to see what can be done. Pay close attention to everything going on in the Master Page while you are in SharePoint designer so you can get a feel for what it contains. Then, after you see what you can do directly against a Master Page in SharePoint designer, you will be ready to learn how to deploy Master Pages to sites through features and solutions.
This series of articles is my attempt to write an article every step of the way through the Master Page modification cycle. Now that we have just given an introduction I am going to show the more specific concepts of SharePoint Master Pages in my next article. Then I am going to go through some of the techniques I mentioned in this comment on modifying the Master Page through Designer or html. Then I am going to go through how to wrap it all up in a feature.
Hopefully by the end of this series you should have a good understanding of how to brand effectively. But, if you want to get a head start, I would suggest looking into the suggestions I mentioned above in this comment.
Stay tuned.... Greg