I have been in new-york twice before and in agoust in coming again with a friend.
We are both 21 years old.
1. Where we could stay at reasonable price in a normal room
2. Is there any discount if we are staying at the same place for like 14 days.
3. If we stay in a queen bed or 2 saperate beds - is the price diffrante?
4. we would really like to go out and see the night life in NY, were we can go that is safe 4 to young girls.

10x

Go to Hotwire.com and look for rooms there. It's cheaper and you'll be in nicer hotels. I would stay in Midtown for sites and things to do. Go downtown for cheap food.
For dancing, try Webster Hall. Can't think of others right now. Don't forget to visit the Kate Spade store in soho.

This is coming from a 24 yr old.

I would try travelzoo.com they have great deals.

you should also try long Island, long beach area, or Hamptons,
Fire Island- Ocean Beach . Great places with summer rental
21 year olds have a blast .

there are a few youth hostels that you can try but the fill up quick

http://dir.travelzoo.com/Lodging.asp?intCategory=23

http://www.qixo.com/index.html?QIXO_...da0cf95b1ba2b1

i have been to parties at Southgate Tower - 371 Seventh Avenue, New York NY 10001-3104 US

and east gate Towers - do a websearch

you want to go to the Village, it is lots of fun around bleeker & 7th is the heart .. also up town around 79th & 2nd .

my girl friend is 25 and could probaly tell you were the hotspots are, im kinda out of the loop on that one, if you want let me know & i will have her contact you

No offense to JJason but please don't go to Webster Hall. It's overpriced, way past its prime and a horrible place for women (several I know had body parts groped like crazy). The same goes for the Limelight.

I'm not sure what kind of music or scene you're looking for but the following places have a good vibe, good crowds and not too far off the beaten path:

Lounges-------
Madame X - Cool red and loungey place on the border of the Village and Soho
http://www.madamexnyc.com/

APT - As the name suggests, an apartment styled lounge in the meatpacking district, very cool place.
http://www.aptwebsite.com/

Live Music----
BBKing's - Sure it's very touristy but it is a nice venue with great sound and the location (Times Square) is very convenient
http://www.bbking.com/

SOB's - Sounds of Brazil in the Village. Just about anybody you see here is gonna be very good.
http://www.sobs.com/

Also check out the Central Park Summer Stage if you're coming during the summer. Pretty wide range of acts performing.

Pick up a copy of the magazine TIME OUT NY as soon as you get into the city. Any newstand or bookstore has it. It tells you all of the cool things that are happening.

My cousin who is 21 yrs old and is extremely hip just had a party at Pianos on the lower east side. Definitely take a taxi to get there -
Good spots in NYC don't get started until 11:30pm -12. Take a nap after sightseeing and dinner.
Check out www.sheckys.com. Click on "shecky's picks"
you can determine what you like.
Lounges with a dance floor are generally better nowadays than clubs.
also check out www.hotels.com for good rates

I work in NYC, and am not so into the nightlife, but when I want to venture to a lounge I check out the Daily News. There's a section where they gossip about what star was seen where, and they always mention the name of the lounge. Yes, these places may be hard to get into, but if you call ahead and try & get on their list it could work out.

For a 21 year-old I think the village would be a great place to stay. My parents stayed at http://www.washingtonsquarehotel.com/
The rooms are small, which is normal for NYC. The prices are moderate, not cheap. The location is excellent, right at the heart of NYU. There are a lot of cheap places to eat in the village as well.

Most of the young nightlife these days is in the East Village and in the Lower East Side just south of the EV. If you're into live music at all, there is Arlene Grocery on Stanton St. in the EV, tend to be local bands, Mercury Lounge on Houston where there's a mix of local and national/international bands on the way up. Irving Plaza and Bowery Ballroom are larger venues with national acts. There are also lounges in the E. Village with both DJ and live music. As far as accomodation, if you are adventurous (I don't mean compromising safety, just that the street looks a bit gritty but very young and hip) there is a Howard Johnson's Express on Houston, right where the Lower East Side, Soho, East Village and West Village meet. Just about all the nightlife you could ever want, within walking distance. Activity is 24/7 around there I hear it's nothing fancy, but reasonably clean and cheap, just looked up August at hojo.com and rates were $99-111/night. Otherwise, give Priceline a shot! www.biddingfortravel.com has all the tips for bids. Have a great time.