Your demands far outweigh your budget. A good fisheye lens alone will cost you about three times what you have to spend... A $25 "fisheye" lens attachment from eBay is really a neat toy rather than a tool or an accessory.

So let me ask you a question - do you want to accessorize your camera just for the sake of accessorizing it, or to look "professional", or do you look for things you may want to use to actually improve your results a great deal?

If it's the former, I really can't help much, because whatever looks cool, is what you should get. If it's the later - I can recommend that you invest your $200 in a photography class at a local community college, if it offers one, or elsewhere. Doing that will get you going and will improve your results by order of magnitude better than any accessory you can buy without knowing the theory and having a little practical experience in photography. If no classes are available, spend it on good books and study on your own. It too will help you a lot!

Remember, that a camera and all that comes with it, are just your tools. The real photographer is you, and only your skill determines what you get. And then once you really know what you're doing, you are not going to have to ask what to buy. You'd probably know well what limits you the most. I would not rush and get more lenses today, before you know what your real style and passion is. That way you won't invest in a wrong piece of equipment.

LEM.
==-Edit-==
Your 18-55 is a good everyday lens to start with. You really don't know right from the beginning what other lens will be your thing. For some people (who enjoy wildlife, as an example) a good reach telephoto will be in order, for others (say architecture buffs) a serious wide angle is a must, yet another type of shooter (sports, indoor or low light photographer) will not be able to live without a fast lens (again, wide or tele, depending on what they do), a true macro lens will be a blessing for the ones taking close-ups, a prime lens is a must-have for portrait person, and a fisheye for those with serious creative ambitions... The list can go on...

So there is really no universal must-have lens for you. Once you get used to the camera, you will know better what part of your current lens limits your creative moves the most, and that's how you're going to know what to get.

All that said - 55-200IS is a very popular choice of a second lens by many beginning photographers. But again, it's not an everyday lens, it's that second lens someone liking medium to moderate close-ups will pick. If I were you, I'd wait and see what is good to get!

LEM.