I'm reworking this guide, so forgive some of the small notes I've placed as a temporary solution to update the guide.
Fishing Basics *edit* -With each cast your chance of catching a small fish is a small percentage, don't be discouraged or jump to "It's bugged!" if you're not catching it. -If you don't loot used bait when caught, you will catch it on the next cast.
You know how to find fishing holes and how to determine their water type. Now you need to learn some things about bait. Such as the different types and where they come from. please ignore the note below about "Special Bait", I've debunked it as a rumor and nothing more.
You're just about ready to start you're fishing adventures, so to make this quicker...Here's a bait cheat sheet along with, the standard fish and where they are caught.
Now go have a fantastic day in Tamriel you magnificent Angler.
And be sure to check out the other pages here.
At the moment Fishing has no reward other than it's fun, relaxing, and gets you achievements. Hopefully the changes in update 6 make fishing more relevant.