I picked up a copy of Brewing Classic Styles based on some recommendations here (great book so far). I did notice that almost all of the recipes have odd LME volumes (8.9 lbs, 3.3 lbs, etc.). I suppose this is when I need to buy a digital scale?
Classic styles recipes use mostly liquid extract, right? My local LHBS sells extract out of bulk drums allowing people to buy exactly what they need.
Check amazon for a scale. You should be able to grab one for less than $20
Yes, LME. Thanks!
Any recipe that calls for 8.9 lbs of LME is overly precise.
I think just getting relatively close to what is suggested is a reasonable course, especially with LME.
But yes. Get a digital scale…for grain and hops! 
All grain recipes are that precise, extract shouldn’t be?
Of course the real problem is sold as a 3.3lb ‘unit’. It’s a little easier to measure DME (and store the extra for later). Generally, 1lb lme = 0.8lb dme.
The precision comes from building the recipe as all grain with round numbers, then converting to extract with the same OG.