At the moment Neoscrypt is only used by Phoenixcoin, but in the near future it will be used by Feathercoin.
When the announcement is made a new Feathercoin wallet will be released that you will have to download and install before the swap over.
For now to mine Phoenixcoin first you need a wallet.
You can get that here http://phoenixcoin.org/
Once you have installed the wallet and let it sync up you are ready to mine.
Go to this thread and choose one of the p2pools to mine at and set yourself up.
https://forum.feathercoin.com/index.php?/topic/7780-neoscrypt-gpu-miner-public-beta-test/
If you have problems setting it up just give a shout and someone will help
Phoenixcoin along with Feathecoin can be bought and sold on Cryptsy