This is extremely basic:
http://www.kpsec.freeuk.com/voltage.htm
This seems to have information on general components involved in electronics:
http://www.design-technology.info/electronics/
Wikipedia has some good stuff to say on series and parallel:
http://en.wikipedia.org/wiki/Series_...allel_circuits
These were based on some quick searches. If you have any questions feel free to ask and we should be able to help.
And remember, the game is MUCH easier with DC power. AC will take a lot of studying to understand fully... things just don't work the same.