http://www.amazon.com/Thinking-Type-2nd-revised-expanded/dp/...
http://www.amazon.com/Thinking-Type-2nd-revised-expanded/dp/...
Then go and get a Typekit account http://typekit.com/ and start experimenting.
Good design (any kind of design, not just web design) requires time and iteration. It's a skill, you have to practise it.