AnnieGetUGun--I do it manually because I have the spreadsheets set up in a particular way for my own preferences, but you could just download the CSVs for orders from Etsy & keep them in the order Etsy has them in.
There's info in this blog post about a free downloadable program that includes a spreadsheet function if you want to try using spreadsheets:
Auto-sum: Adding Up Your Totals
http://www.gotogreatpanes.com/blog/2012/06/14/autosum-adding-up-your-totalsAnd there's lots of free tutorials online for how to work the software.