I just have a huge, fairly free-form document file with recipe info. I tag recipe names with codes like ***** (that's five asterisks, not something a moderator did here, lol) for a favorite finished recipe, *IP for recipes in progress, **TRY for variations I want to try, XXX for other people's recipes (so I don't accidentally post them somewhere as my own), and so on. I keep all my mixing notes for later reference. Here's an example of a short one, notes that led to Chocolate Peanut Butter Milkshake:
"2% Vienna Cream, 1% Hazelnut=strong raw nut+vanilla; added 1% AP:sweeter and smoother; now 1.5% AP + 1% Caramel = sweet peanut butter! or pb cookie dough, too much vanilla; make cookies? Added 1% Cookie: pb cookie; Add brown sugar xtra 1%: baked pb cookie; add more hazelnut and 2% cocoa: hazelnut flavor returned, cocoa is sweet! restart.. 1% Vienna, 1% Caramel, 1.5% AP, .5% Hazelnut - milkshake **TRY with choc/cocoa for pb-chock milkshake"
(the finished recipe follows and looks just like what I post here, including the descriptions)
Disorganized as that probably looks to everyone else, it has everything I need, and I can find anything I'm looking for pretty quickly, and I use it constantly. I don't bother printing it. I have a sizeable network of computer equipment and automatic, cloud-based back ups.
I also have a spreadsheet that lists all my flavorings, standalone percent, descriptions, whether/how much 'custard note' ingredients they contain, a few other things. It looks a lot more organized than my recipes super-document, but so much is in code, it would be meaningless to most people.