Losing a limb/paralympics

I think you have to be very careful about choosing an event in the paralympics. While the loss of a right hand might be a major loss to you or I, to some of the athletes it would be nothing. As such, there are strict eligiblity criteria and the following site is worth a look. There is something for eligibility in each criterion if you click down. Swimming might be a possibility.
http://www.paralympics.org.uk/landing.asp?section=000100010005&sectionTitle=Sports

I haven't met a lot of people who have lost limbs, but those I have met have almost been proud of their loss. One I know introduced himself as "lefty" and another demonstrated his false leg by knocking on it. I imagine the ones likely to become offended are those that are still coming to terms with their handicap.

I'm not sure that a traditional "hook" is widely used today. Most people will end up with a myoelectric device that offers at least some rudimentary pincher grip.
Look at a web site for Otto Bock prosthetics. These guys make some pretty amazing stuff, including the C Leg. The first computerized prosthetic knee that allows the user to handle stairs naturally, without a "step to" gait. One saved a guy's life coming down out of the WTC on 9/11.
Also check out the Paralympics web site. That'll give you many answers about what they do.

EG

I swam with a guy in college who was very involved in the Paralympics - we even went to Atlanta to see him compete, which was pretty cool. I think someone who's only missing a hand would be at the highest functional level (S9, I think it was called?)

My friend was missing both legs below the knee and had a withered right hand - he had all sorts of prosthesis, including a crappy old pair of legs without feet that he wore around the water. (He was also a trickster, and used to do this like stick his 'feet' under car tires to freak out the owners.) He could've worn a prosthesis on the withered hand if he'd wanted to, but he made do just fine with the other, so I don't think he wanted to bother with it.

The guy was pretty impossible to offend, although I did a good job the day we met by assuming he'd swim slower than I did on the first day of practice. He blew past me to show me how wrong I was lol.

That said, he'd been born with his condition, it wasn't a loss, per se, so I imagine it'd be different for someone who had.

HTH

Different people develop different ways of dealing with it. Some develop a sense of humor about it; the trickster and the gallows humor sping immediately to mind. Some become overly sensitive and yet others just go about the business of living life.

EG

I saw Josh Sundquist, a former paralympic skier, speak a conference. He lost his leg to cancer as a child--and well, watch the video on his site. Absolutely amazing--and I saw this speech in person. He has a book out that you can get that will probably give you some things to think about. If memory serves, I think there was a photo of him with an artificial leg, but he doesn't need it (like I said, watch the video).