Practical Question I have working for Indian SEO sites, is it possible to get data how much traffic we are getting from particular region or state ? It is my client requirement.
Google analytics new version gives you exact city also. It gives a detailed view of traffic coming from each city. Also you need to change the target audience to India when you submit site to google webmasters. That really helps to promote your site specific to that region. Even better get a .in domain and your target audience will be from India.
There are many ways to estimate the traffic amount, source and all other important facts and figures so they one which can help in improving the website to webmaster is definitely Google analytics
I don't think that there is any other good tool then Google analytics new version, it gives you good detail about traffic sources and region from where you are getting that traffic.