Would a '79 CB750 work well for a first/commuter kind of bike? Anything I should know about one I might go look at, say tomorrow sometime? 
It's a little more displacement than I was originally looking for, but I figure a '79 750 isn't gonna be any more powerful than a '90ish 500, which IS what I was looking for.
As I recall, 79's were twin cams and they used shims for valve adjustments, which makes the job a little trickier than on the older ones.
Specs: http://www.bikez.com/motorcycles/honda_cb_750_k_1979.php
'79 is DOHC, which makes valve adjustments tougher, but they almost never need to be done.
They're pretty solid bikes. Not too much for a beginner, provided you're comfortable with its weight a low speeds. It's no Goldwing, but it's not a featherweight, either.
They're not my cuppa, but if it's well cared-for, it should serve you well for commuter duties.
If it were 1979 and you posted this, people would be like "what is a internets?" then they would tell you that it is way too fast for a new rider, that you would kill yourself, blah blah.
Same thing happened when I got my first street bike - a new FZR600 back in 1989. Now it is a bike that people would recommend that you start on before moving up to a Buell Blast.
If it is in good condition, the forks, shocks, brakes and steering head bearings are all in good shape, then a CB750 is should be a great first bike. I assume that you are not 4'6" and feel comfortable sitting on it and can lift it off the kickstand.
www.cb1100f.net has every resource you could possibly need for that bike.
(you'd never guess I'm 79cb750f on that forum)
Start out with a CB 350 like everyone else!
It is a boat of a bike. But soooo cool. If you are worried about it being too powerful, you're probably in the right mindset to begin with. Just bear in mind those breaks and suspesnion are a little behind the power curve of that engine.
But if you get it, never never sell it.
