I was wondering about the workings of the rw pad. I assume it is to signal to the motherboard when the processor wants to read data from the memory and when it wants to write. So power on rw means read, and a 0 means write? What about the situation when the processor wants to neither read nor write but is just processing some stuff internally?

Where can I find a short description of what the other pads do(besides the data and address pads)? Which of the pads are used to send information outwards and which are used only as inputs?

Yes, 1=read, 0=write. And when it's doing internal stuff, it sets it to read.

For more information, check out this page. I recommend the two books at the bottom.