Users teaching users
I told you previously that Arduino was not just a board and a compiler. One of the things that I personally think has made Arduino become such a big platform is its online community.
On the Arduino site, you can find not only a traditional forum (http://forum.arduino.cc) where lots of users share their projects and troubles and help others, but also one of the sections I like the most: the Arduino Playground section.
The Arduino Playground section (http://playground.arduino.cc) is a section of the Arduino website where users publish information about ways to connect Arduino to other devices of all kinds, linking to their own websites in most cases filled with information about the project they have worked on. It is some kind of collaborative showroom.
For me, the Playground section is, perhaps, the most valuable site you can go to whenever you are beginning to work on your own project. There are plenty of possibilities that you can find in that piece of information that can serve you as a starting point.
