You need software!
If the OP reads a brewing book first, he will not need software to perform basic brewing calculations. The calculations encountered in recipe formation do not require a great deal of mathematical maturity. Brew house calculations are middle school level at best. I have formulated several hundred batches of beer without the aid of brewing software.
I don't disagree with you, but software is cheap (and there is even some free stuff) especially when you compare it to other parts of the brewery and my time. I can't imagine not using software.
imagine not using software. It starts with me hunting for a pad and pen, and ends with me going "eff this" and logging onto my computer/tablet/cell phone about two minutes later. Even if there was no brewing software, I'd just build an Excel spreadsheet that does everything I want. That's just how I work. I have a tendency to spend an hour building and tweaking a spreadsheet to solve a 20 minute problem, knowing the next time it will only take me 30 seconds.
I appreciate and respect the skill of writing a recipe and calculating by hand, but I'm kind of glad I started brewing at a time where that isn't necessary.