Get a copy of Robert Hurst's The Art of Cycling: A Guide to Bicycling in 21st-Century America from your library or bookstore. He covers the points mentioned by the posters and a number of others. There are other books, but Hurst's book is one of those which is practical and not dogmatic. I'm a better cyclist for reading it.

If you like courses and one is in your area, the League of American Bicyclists offers courses and has some online materials.

Another frequently cited link is BicycleSafe.com