What your talking about is really, not that difficult, what camera system are you shooting? I have a couple of cameras that I use for Weddings that work quite well as they have correct flash exposure information displayed in the viewfinder LCD.
Using a two or three light set-up mounted on tripods can be very effective, with a slave, and can also be done without a flash meter.
Let me know if I can help. I will be happy to let you know some of the 'spur' of the moment put together set-ups that I have done and helped me save a few shoots.
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