If I create blogs in our local national language (Hindi, Tamil) Is google will place adsence in my blogs? or It will allow only English blogs/websites?
you can find the list of languages supported by adsense here: https://www.google.com/adsense/support/bin/answer.py?hl=en&answer=9727 But, I could see blogs in that languages. I don't know why google not included in that list.
Not sure.... One of my client has a Gujarati Blog and he kept adsense for one day. But the very next day he got reply from Google that "you cant place adsense on this blog. Reason is Language mismatching." I think you should have some English Words to place Adsense on such site.
some language wasn't support for adsense, in my experience i have a blog that used bahasa (indonesian language) and the ads was never come (only the Public Ads)