I still am unsure of the direction that I want to take my rack.

Not necessarily the best strategy... but it is quite common

I have just been adding modules as I could afford them.

that's generally what most people do, at least to

I saw a video of someone that had the case USB connected to a computer and was running some software to control the VCOs. Does anyone know if Garageband can do that? Or is there another free program? I'm not sure I would always want to do that but I would like to give it a try.

what does reading the helpfile/manual for Garageband tell you about setting up a midi track and sending the output to a midi device?

there are quite a few free DAWs available... google is good for finding out what they are

"some of the best base-level info to remember can be found in Jim's sigfile" @Lugia

Utility modules are the dull polish that makes the shiny modules actually shine!!!

sound sources < sound modifiers < modulation sources < utilities