One thing you want to consider is whether or not you are going to make prints. If all you are going to do is look at them on your computer, then any cheap model will do. If you want to print these off, make sure you get a camera with at least 1.2 megapixels. This will print a nice 5x7 print that looks really good. Make and models are just personnal preferance. I have several models, and each has it's own good and bad things. I like the models with zoom lenses that are at least two to one not digital zooms. Start there and work your way up. Also look at the storage memory. There are different types here also. Each has its good and bad points. I like the Smart card and use up to 32 megs of card memory, and I can shoot all day long and not have to carry extra memory cards. Well I am not that lucky to catch lots of Steelies. Memory card right now are fairly cheap and are easy enough to change, so pick up what you can afford. Kodak is good, Olympus is good, Canon is good. These are the three that I have, and I like each. Some use a computer disk 3 1/2 floppy, for a memory card and these are lower res pics. This is the only one I don't like, but it was my first. Go to a good camera store and look at the different features and take a few pictures and have them show you the differences. Make them give you a print right there. You will notice some big differences after the printing....... Good luck. I hope this is some help!
One more thing is too go to www.Webshots.com
and look at the different fly fishing pictures there in the community pages. Ask the people who have taken the pictures what they are using!