Learn to Program
There are many ways to learn to program. Many online tutorials are available. I would suggest the languages Javascript and Python. It is good to be able to get started quickly without much setup required before you start programming.
Python tutorial at python.org
Dive Into Python is a free Python book for experienced programmers.
This site has tutorials for a number of languages. I would suggest Javascript and Python.
Programming in a web browser:
Skulpt–an in-browser implementation of Python
The Codecademy tutorials are also online and interactive
Videos:
Douglas Crockford on JavaScript
Books:
JavaScript: The Good Parts by Douglas Crockford
Another option: learn Processing. Processing is Java plus an interactive development environment that makes it easy to get started and get quick feedback on a program.
Overview on Wikipedia: Processing