where do people get these diagrams from?

 

chiltons or hanes service manuals. I'd suggest picking one up, their very handy. Though I'd recommend hanes, my chiltons one isn't the best

 

people are finding them online though. are they from those chiltons repair manuals on CD?

 

do happen to have wiring diagram for 97 civiv coupe

 

They are Helms service manuals, also known as factory service manuals. Unfortunately, it is against the rules here at H-T to post links to them, since it is copyrighted material. They really aren't hard to find, when you're looking for ones of specific cars.