James, Amazon.com is your friend; browse their used books and videos. I would suggest if you never got any formal Tv training, pick up a used copy of a college TV textbook, any edition of Zettl is good, I think. Just to build a bit of a foundation, understand. Then move on to editing-specific books. The editing books by Walter Murch are a popular favorite, but by no means the only ones.
The COW has a ton of free tutorial materials and links. You can also find some at Video University as well as the DJTV section of Digitaljuice. These are all free.
Learn to watch TV and movies critically. Watch the DVD with the sound off, and make notes on the angles used and when and how the editor chose to switch them. Attempt to guess which camera will switch when. Watch soap operas with the sound off, just look at how the sots are framed and the timing of the cuts, look for the rythms in it. Do the same thing with talk shows.
Those are all free things that will help you, but you have to do more, you have to do things hands-on. Take what you’re learning from these resources and make up some projects to practice the techniques with. It doesn’t need to be fancy at all, simple home camcorder footage or scraps of things taken off Tv will do, just get some raw material together and start working with it. Nobody will ever see this but you. Shoot two people talking and re-cut it. Practice things like L-cuts, cuts where the video or sound changes independently with a time offset. Practice the art of montage, taking two separate images and juxtaposign their order to derive a new, third meaning from them. Practice simple frame-matching between a wide shot of soemthign and a close-up of it.
The more you do, the better you get. I suggest you do a few month’s of this, up to a year of this before you take a paid class. The short classes are mostly to teach you what button does what, but not WHY. The WHY and HOW are what people actually pay us money for, anybody can just push buttons.
Best wishes and good luck.