Also the O'Reily Michael Margolis book The Arduino Cookbook.
Get the book, read the book, do the experiments.
Also Google Arduino programming...
If all else remember this computers are devices that follow instructions explicitly.
which means if you tell it to jump off a bridge, don't get between it and the bridge.
I hope that help one remember they are literal devices that follow long series of
instructions and do not always know your intent only what was written, write carefully.
Personally I like to use the local IDE on my linux box. Its a fairly concise tool but
how to drive it requires one to understand the Arduino Dictionary. An example
what most programmers call a program to arduino users is a Sketch. learn the
concepts is stepwise fashion and its interesting if not easy.
Remember Arduino was designed for people that want to make things and not
become hardware or software engineers.