CSS Question

Ok, I know with css styles you can change the look of form fields, change their color etc. Is there a way to add to a CSS style a list of words where if a user types it in it will turn bold, or turn blue or something, within a textarea?

as they type? Not that I know of but you should check out javascript. I might be able to.

As they type. No.
That would require some client side scripting (javascript as said before )
But, you can set it so the text field itself is bold. I won't give you the code cause it would probably be better for you just to learn it yourself (it's terribly easy).
So here's a link instead.
http://www.westciv.com/style_master/academy/css_tutorial/index.html
It's a wonderful FREE CSS tutorial, you can buy the non free version, it is also very very nice (although I like the free versions colors better hehe).
Good luck in your quest