I have gone over this in my head and then started asking those who really know.
Software (the 21st century answer)...but isn't there more than one way to do it?
Yes, but narrowing down to what to buy and finding time to do it is the hardest part.
I jam with a music computer software guy who can get any sound pretty quickly with his $500-$1,000 dollar software music suites but the talent is what he got from his 4 year music industry degree. Short of enrolling in an expensive university program on how to record and get sounds, then make it a serious hobby where you don't mind delayed gratification.
His best advice when I mentioned wanting this tone or that tone (on guitar) he mentioned start with the basics (Macbook Pro and large studio monitor 30" inch or so, and not focus on guitar or amp that much) and then pick among a whole host of suites (where the guitar sounds definitely are) but commit to one or two suites at most and put in the time to learn
how to tweak it. That's the core you can't do without. Other suites, monitors, speakers, soundproofing, all come later and a lot of that is personal preference.
Once in with good computer/music setup, it's incredibly daunting learning the software
and it takes a long time to take a guitar signal direct and shape it, but shape it you can in so many ways you can't with amp and stomp box effects. It's like a factory where it takes time to set up but once there, you can really start producing sounds you like easily with consistency. Consistency is not always there with stomp box effects and a certain sound you dial in one day may not be easy to replicate.
Now all that being said, I have seen where a serious songwriter or guitar player gets into the software computing side so much that their music starts sounding like a muzak chip. Their brain gets so focused on the technical that they actually lose their creativity and even drive for creativity. Just a warning.