does anyone have any favorite books for learning arduino language. I know its related to processing and C blah blah yea .
If you've done some programming before you can just read-through the [u]Arduino Language Reference[/u], and then maybe work-through some examples.
There are some "starter kits" that come with a book and example projects, but I don't have one and I'll let someone else recommend one. The [u]Getting Started With Arduino Page[/u] has information on a starter kit and a book.
[u]cProgramming.com[/u] is a good place to start learning Standard C & C++ with tutorials, book recommendations, IDE/compiler recommendations, etc. But, Standard C and Standard C++ expect you to have a keyboard, a video monitor, and disc storage so a lot of it does not apply to the Arduino. (i.e. The examples in the tutorial would run on your computer, but not on the Arduino.)
How to make sound with arduino usually brings up hits on stuff like a guy making a piezzo buzzer to detect tones....
And, how is that different from what you want?
When you say "pressure sensor", I think of something that senses water pressure or air pressure in PSI. First you need to find a pressure sensor. Then you can figure-out how to hook it up and how to read it because every one is going to be different.
Your program will probably be an [u]if-statement[/u] in a loop. i.e. If the pressure sensor is triggered, or if it senses enough pressure, an output pin with a buzzer is turned-on, or a tone is generated.
The two most important concepts in programming are conditional execution (if-statements) and loops (doing things over-and-over, usually until some condition is met). Once you understand those two concepts you can start to understand how to structure a program.
A "buzzer" has electronics built-in to generate the tone when power is applied. A regular piezo transducer is a kind of speaker and you have to feed it a tone.