i'm in need of the same thing and have no idea how to do it. i want to have my touch screen upfront but i have to lcds in my back headrests and i can't figure out how to split the signal between the three
You need a converter box, LIKE this one.
Im sure there are many that would work. You could use a vga splitter, then run one to the vga monitor, and the other to a converter. BE mindful of the specifications of such devices; not all are compatible with all resolutions, and not all provide multiple outputs SIMULTANEOUSLY.
EDIT: From the specs of the product linked to above: Output: Simultaneous (with VGA Splitter Cable) on VGA Monitor and to: Video Monitor/Projector, TV, VCR, etc
Carputer status: [-*---------]
Im thinking laptop...