Hi Johnny! Welcome! I think most of the information you need can be found under the topic NYC Fan Meetup? A group of us are getting together in a couple of weeks and we're planning to take a few photos of a couple of places, and all the info you need is there, I believe. Enjoy your visit.
Oh, fish-like Lady
I don't think so Bro, she's a Lady, Lady, Lady, Lady
No, no, she's a fish that's just a little bit
If you go to Google Maps http://maps.google.com and do a search for 'conchords locations NY' you'll find a bunch of places! - I can't vouch for their accuracy as I'm on the other side of the planet, but... maybe someone else here can?
I'll try and attach a couple of jpgs of places I found that way (If I can figure out how!)...