Even with the noblest of intentions, I don't know how proper it is to take the hackernews brandname for your own site. At the least I think you ought to consider putting a disclaimer on an 'about' page somewhere stating that you are not affiliated to HN and YC.
On a positive note, nice job! It looks like you're getting a bit of traction already.
"If someone can tell me how to put a disclaimer in the footer"
The right way is to change the name. If I start a site called Google India, or even Digg India, it isn't enough (legally or ethically) to have a disclaimer in the footer, even if I am running a non profit. You keep repeating the "this is not for profit" sentence. That isn't a valid defense against brand name abuse.
At the very least get permission from the owners on the original site before starting a new site by adding an "India" to its name.
The last thing "Indian hackers" need is a reputation for ripping off other peoples work/brands (As if the outsourcing horror stories aren't enough). Use the open source code, by all means. But don't copy the name.
I am an Indian developer and I think such unabashed copying of a popular brand is shameful. YMMV.
Even if the source was free, the brand need not be and in that case HNI would be plain illegal.
Its been mentioned here that Firefox is open source but they own the brand. If hypothetically speaking, you start distributing Firefox with its proxy settings customized for Indian ISPs and call it Firefox-India, the chances are high that you will hear from lawyers.
That explains a lot. Your site is still called Hacker News because you don't even know how to change the name. I assume the only reason the site isn't orange is because that information is stored in a CSS file.
Then you should'nt have gone public with it in the first place, until those issues had been resolved. I hope I am not being unreasonably critical. Regardless of the fact whether it was legal or not, things like these just leave a bad aftertaste and you would want to avoid that as much as possible.
On a positive note, nice job! It looks like you're getting a bit of traction already.