how we can mine this coin??
1. It's not really a coin, but more like a token, or a platform even.
2. You can't 'mine' it, it's proof of stake, not proof of work. Transaction fees are rewarded to people that leave their wallets open to help secure the network, it's called 'forging'
http://en.wikipedia.org/wiki/Nxt#Forging It is possible to lease your amount of NXT to a bigger 'pool'. And with the new 'Monetary System' it will be possible to create Proof of Work currencies on top of the NXT blockchain.
Correct, all Nxt are already in existance, no new coins are being mined.
But you can mine some SHA256 or scrypt coins for Nxt. Just go to hashrate.org and point your miner at one of their servers, they will switch to the most profitable coin, and exchange them for Nxt automatically.
