If you really are multiplexing the LEDs, then you will have the anodes of several LEDs connected together and only one of the corresponding cathodes will be driven low at any one time. In this case, you only need one resistor per bunch of connected anodes, not one per anode.
I'll have to look into that. At the moment I don't see any downside to multiplexing at all, just seems like the commonsense route. Anyway, I'm thinking the ShiftOut example can provide most of the basic information I need at this point.
Thanks again for answering my questions so thoroughly, and I'm sorry if they've been asked before.