I've found iFixit to be a useful and entertaining site. It has many repair manuals and disassembly instructions for computers and electronic gadgets.
When I was a kid, I liked to take things apart to look inside and to have a resource like this telling me how to take things apart without breaking them is a godsend.
I've consulted the site when I poked around and upgraded two Macbooks. Before looking at the instructions, I was afraid I might break them but the instructions were very helpful and I could follow them quite easily.