Hi,
Don't worry about Servo.h yet. A main reason for "Libraries" is to pull together details out of your sight, but help you use them.
Take a look at the http://ArduinoInfo.Info WIKI to start:
http://arduino-info.wikispaces.com/Arduino-What-IS-it
and
http://arduino-info.wikispaces.com/YourDuinoStarter
@LarryD suggested http://www.allaboutcircuits.com/ which is a good Electronics starting place.
I think the best basic Electronics book right now is MAKE:Electronics My list of good/better books is here:
http://arduino-info.wikispaces.com/Arduino-GoodBooks
For programming, "Programming Arduino - Getting started with Sketches" by Simon Monk is very good.
Go For It!!