I wouldnt pay a cent for catering software, 3000, crap!!
Buy a 6 pack, grab a lawn chair, write up some formulas in excel, you're good to go. Or if you have some software friends like me, get them to write a whole program for you for free
..
But honestly, I do all my work on excel and in my head, maybe I am just good with numbers and tracking I dont really know. Excel has no frills, its dirt cheap, easily modifiable and used by the biggest of corporations because of the simplistic features and advanced.
I suggest spending some timing becoming familiar, it might save you thousand, but this is just me.