Jann is absolutely correct, the crop factor removes much of the fishiness.
I
love my Zenitar 16mm fisheye. It's available straight from Russia via eBay seller "zenitar" in Pentax, Pentax screwmount (M42), and Nikon mounts, and I believe some sellers sell the M42 one with an EOS adapter for Canons, and supposedly a few even have "real" EOS mounts on them. It's cheap ($125-150), has quite good optical quality (probably not up to $500-600 fisheye level but still very good), and is a ton of fun! But, it is
fully manual. Manual focus, manual aperture, manual everything. You need to have your camera in full manual mode and "stop down" to meter, to have it set the shutter speed and ISO.
The manual focusing is really not much of an issue, though, because pretty much everything farther than 2.5' feet away is in focus. Talk about your depth of field! It's also a fairly fast lens (2.8).
Pentax makes a 10-17mm fisheye that is well regarded, and this same lens is apparently now being sold by Tokina in a Canon and Nikon mount, so is an option if you have the money. (Over $500.) Supposedly this was, at least for a while, the only lens that gave you full 180' fishiness on an APC-sensor DSLR.
Which leads up back to the crop factor. If I put the Zenitar on my 35mm Pentax, I get 180' of vision. (I'm picking up my film tomorrow so I should have some examples to post after I scan them - it's really something! You have to be very careful that your fingers and even your feet don't end up in the photo!) When I put it on my DSLR, I get closer to maybe 100' or so, and the fish effect is less pronounced because the really curvy edges are cropped off.
Here's an example of a shot taken with the Zenitar. Here the fishiness is fairly apparently due to the straight lines near the edges of the frame.
Here's another example.
The wide view and huge DoF make it a terrific lens for taking on-ride photos (as long as the light is fairly constant, because of the manual metering):
As you can see, in some photos, it's hard to even tell that it's a fisheye.
I would love to move up to a "true" 180'-on-DSLR fisheye in the future, but for the moment, I'm loving the Zenitar. It's a blast and relatively cheap. I also used it a bit for fireworks photos - I often cropped the resulting photos, but there was no concern about some fireworks going up too high and disappearing out of frame!
I also hope to pick up a fast non-fish wide-angle - ideal would be maybe an 18mm 1.8 or so, I'm not sure that one is available for my camera at this point though. Actually, I think there is a non-fish 16mm 1.8 but it's not cheap.
As for macro, I don't have a "true" macro lens - one of these days, but I'm not really into that at this point, and I definitely don't think they're much use at Disney (outside of maybe the occasional flower photo).