Underwater photography for a Nikon D3100?

I'm 14, and I simply love photography. We travel to Greece every year to visit family, and I'd love to capture some of the underwater sea life, not to mention surfers at our beach. For the most part, all of the underwater housings I've looked at are expensive, and I was expecting that, but if I'm going to do this, I want to get something more reliable that a Dry Pack bag. Although, I don't know if getting a housing is the best option. What about getting a point and shoot then buying an underwater housing for that, or a GoPro Hero 3? I'm not sure about the image quality compared to a DSLR, but most of the water I would be shooting in would be pretty much crystal clear, expect for the Atlantic waters for surfers. What would be the best for me? I do have a bunch of money saved up and have been wanting to look into this for a while.

How to adjust the shutter speed on a Nikon D50?

I have a d50 but don't know how to do much other than snap regular pictures.Id like the shutter to stay open longer to show action/movement and for cool effect but don't know how.

Does anyone know how I can achieve this?

Help needed! - can't decide what to do, need proper advice?

Although it might seem like I already know the answer to my problem, I'd still like to get some advice.

The problem:

I've got $1, 200 and I'm trying to decide whether to buy a camera (Nikon D7000/7100) or upgrade my PC. Which if I were to do so, it'd be a total of $1700 for the PC (I already invested in a graphic card - $412).

Photography for me is a hobby as of right now; I'm studying Graphic Design and I do like the creativity involved with photography, specially for Long Exposure, and night landscape which are my two favorite categories/techniques to do. As for the computer, I'd like to say I'm an above average gamer, I use my current computer almost every single day for 2 things only, browse the internet and gaming.

Now, I already have a camera (Nikon D5000) and a gaming PC (quad/8gb ram/GTX 770, etc.) but I'd like to upgrade to something a little better.

Bad thing about the camera is that it's family borrowed, so I just have it for an indefinite amount of time until the person who owns it wants it back, so technically I do not own a camera of my own.

Feel free to advice me in anyway possible, will listen to anything and everything, thank you so much in advance!

Should i save up for a macbook air laptop or a nikon d3100 camera?

So i want something that i can save up for. I'm 13 and i want one of these things, they are both pretty expensive and i'm really into dancing and theatre so i was thinking the camera would be good for pictures to bring to auditions but that laptop would be good for school. What would be better to get?

What is the exact mm of uv filter lens for my nikon D5100 with 18-105mm lens?

I have nikon d5100 and with AF-S DX ZOOM-NIKKOR 18-105mm f/3.5-5.6 G ED VR lens.
pl tell me the exact size of uv filter.
secondly, is it necessary to fix a filter and why?

Hookah smoke and camera equipment?

I'm a photographer, and this Saturday I may be photographing a friend's performance gig at a Hookah bar. I have never been to a hookah bar and do not know how smokey the bar can get. I shoot with a Nikon D5100 and a Nikkor 55-300mm f/4.5-5.6 lens. Will the hookah smoke harm my equipment? I will have my camera bag handy to contain the camera when it is not in use and keep it safe.

I have a Nikon D3100 but I'm having problems printing my pictures

I'm not able to post them on Facebook or print them at Walmart, instead of showing IMG it's shows DSC. Could this have something to do with it? If so how can I fix it to where I'm able to print them & post them?

What camera to take on holiday?

Going to Tunisia for a week, was wondering what camera will be good to take also giving it as a present to my boyfriend who is going with me. Thinking about maybe Sony cybershot HX200v (18.2mp, 30x optical zoom) or Nikon D3100 digital SLR. Or any other recommendations. Camera will be used casually, price range: £400 max! Any suggestions will be greatly helpful cheers.

How to work a macro lens reverse ring?

I just bought a lens reverse ring for my Nikon D7000 18-105mm lens. I've tried adjusting the aperture, zoom, and shutter speed; everything is still out of focus.

Idea for short films on the beach?

I'm at indian rocks beach in FL and I would like to shoot a short while I'm here. I have a nikon d3100 and a dslr rig and have some experience with a youtube channel called ZigelnikTV. If you have any ideas you are willing to share, you will be in the credits
Specs: 2-3 minutes long
Silent
Comedy