RS232 Breakout Box Schematic

I'm looking for a schematic on a standard RS232 breakout box. I want
to use this schematic to build my own breakout box. I know I could buy
one from Radio Shack or somewhere else but I want to build my own.

I have some information to start with but I'm missing vital information
with regard to any resisters, transisters or any other components that
are needed in conjunction with the LED and pins.

If someone has any links to other information on the web that would be