Least expensive circular fisheye lens under 8mm?

I will be buying a Nikon D3100 soon and I really like the effect of fisheye lenses, particularly circular ones, such as the Sigma 8mm lens, but I can't afford them.

Does anyone know of any fisheye lenses that are 8mm or under and is sold for under $100?
They don't have to be high quality ones; I would just like fisheye lens for its effect.

And they should be able to be used with a Nikon D3100.

How to use a fast shutter speed in a dark room?

Whenever I have a fast shutter speed on (and large aperture too, like 4.8), my images come out dark. Is there any way to change that (other than larger aperture)? If so, how? Btw: I have a Nikon D3000.

Nikon Warranty Crisis?

I purchased my Nikon d90 is november 2009. I purchased it off ebay.com as a packaged bundle with 5 lenses, a tripod, a backpack and a 3 year warranty card. I was unaware at the time my purchase arrived, that i had to activate my warranty card.

At the beginning of november this year, my shutter stopped working. It jammed every time i'd try to take a picture, and would either give me an error message or only take the bottom half of a picture. When i went to file a claim, I realized I had to activate my card. I couldn't find my original receipt anywhere, no matter how long or hard I looked, so I put in approximate dates opn the warranty registration. They now want a copy of my original receipt. And I don;t know what to do. I paid almost $2000 for the camera and warranty, I don;t think I should have to jump through hoops, when I registered the card it even said what type of insurance I had on it. What should I do? I've already sent the camera tro Nikon. I don;t want to have to pay to fix the shutter when $200 worth of insurance should be mine.

Added (1). The transaction is not on paypal. I didn;t buy the insurance from a store, it was a packaged deal from some company in boston or something on ebay.therefore there's no 'store' to return the insurance to.

Turn off red eye on d7000?

When I use a sb 900 flash it keeps doing like two mini flashes before the main one which I assume is for red eye. How ever I hate that as it makes me miss shots. How do i turn that feature off? Do I do it on the sb900 or so I do it on the nikon d7000? And how?

I just got a new Nikon D90 and i can't get it to charge, what do i do?

I just got a really nice camera for Christmas, and it was used and i plugged it in to like 4 different chargers, and it won't charge so i don't know what to do D:
The camera is a Nikon D90

Added (1). It Came With a Charger And An Adapter that Says Palm On It, But There's no Charging Light That Comes On.

Added (2). Okay I Just Plugged It Into The Usb Cord, and the Adapter, Into The Wall But It Still Won't Charge, Even With the Charger I Got It With, But I Don't Know If It's The Right One, I Got It At A Pawn Shop…

Added (3). Yeah I Don't Have A Charging Station, all i have Is a Cord with an adapter, It Didn't Come With One Of Those:/

Added (4).

This Is How I Have It And It's Plugged Into The Wall.

Added (5). I Went And Bought A Charging Station Thing, Like This

Am I All Good Now?

I used Iklear on my nikon d3000, is that ok?

I heard that Iklear was good to use on lenses and everything and I've used for my screens on my phones. Is this okay?

Settings for Outdoor Christmas Lights?

I have a Nikon D3000. I was just wondering which settings I should use to get the best outdoor christmas light pictures. It will be dark when I go and I only have the standard lens that came with the camera. Any help would be greatly appreciated!

Canon t2i, pentax k-r or nikon d3100?

I've been doing tons of research on dslr cameras and have decided that it's down to these three. But I honestly can't decide which one I want to get. Video isn't really very important to me but it would be a nice extra feature to have. I'm mostly interested in travel photos and indoor photos. I might be shooting some action photos as well but not very often. Will the major difference in megapixels between the t2i and the pentax affect the photo quality much? Any advice on which I should choose if they are all basically in my price range?

Am i a good photographer?

I wana major in photography.i'm only a sophmore in highschool. I use a nikon d5000. Do you think ill be able to? Am i a good photograpgher?
here are my pictures.

Why Nikon D60 then D7000, then D90?

Why is Nikon releasing funny sequence D60 then D90 then D7000 then D2100,… Why is this unstable numbering… Anyone can explain please?

Added (1). I tend to disagree with the Jen's answer simply because big digit models began to come before the D60 and D90 hit the market. We need the real story to avoid making a wrong choice. I know some brands use two parallel releases one w high content of plastics and the other is of titanium or some tough materials; keeping the engine same.