I'm using my Olympus E-PL1 micro 4/3 digital camera as a director's viewfinder. I set it on 4:3 which is very close to 5:4 LF. (ie. 20"x15" vs 20"x16"). I switch the LED view to BW if shooting BW film. Some cameras have filter settings. So you can look at the scene with a yellow or red for example to get an idea of how it would look with a real BW contrast filter. Then I use the zoom to find the framing I want. The zoom tells me what LF lens I should use. I initially compared the LF lenses against the zoom range on the horizontal of the digital camera. I ignore the vertical figuring width is more important usually. I then "mark" the zoom on the digital to the equivalent width angle of each of my LF lenses. The digital camera's zoom covers me for my 300mm 150mm and 90mm. It doesn't go as wide as my 75mm. But I can tell at 90mm equivalent if I need something wider and I'll use the 75mm. So if you would do this for 5x7, check the width against the digital, unless you're shooting portraits. I also snap a picture for reference.
I might take a quick video clip and might dictate the settings, movements, and any other comments rather than write them down in a logbook, especially when I'm rushed due to changing light. I transcribe the info afterward.
Although a somewhat separate issue, I started using the digital camera as a meter using its spot, center, histogram, and the LED display to find the exposure settings which I then transfer to the 4x5. Taking a picture records these settings on the digital photo for reference later.
A couple of things to keep in mind. Micro 4/3 aperture on my camera only goes down to f/22. Most smaller P&S only go to about f/8. So using a small P&S becomes more calculating. Also, the ISO of the digital camera only goes to 100 and I sometimes shoot Velvia 50. So you have to play with the exposure in your mind when transferring settings to the LF camera. Of course, if you don't intend to use the P&S as a meter, all the other functions as a viewfinder are still available. A small cheap P&S also fits in your breast pocket or from a neck lanyard.