This is a somewhat sanitized version of what I was doing:
Code:
https://docs.google.com/spreadsheets/d/19SeufTEGJACLaVa1UX-iD-7-gVuwc48CQvtTsoWKsS0/edit?usp=sharing
I decided to put together something more useful for other people though:
Code:
https://docs.google.com/spreadsheets/d/1sjtN1d5Brp5CEZFao-AXtUykqIpRZn8-bxQa_e7Eqmo/edit?usp=sharing
You should download the the sheet and open it with Excel, or download it and reupload it to Google Docs so you can edit it.
I set up some default categories on the first sheet, but you can add as you see fit. Make sure you don't delete it otherwise it'll break the rest of the sheets. I threw together some fake numbers on the Example sheet so you can see how it all works. Select a category from the drop-down (populated by the first column on sheet 1), fill out Item, Date, Price, Quantity, and Location. It's smart enough to update Total, Category Totals, and Total Expenses on its own. If you edit those columns yourself (and you don't know how to use Excel very well) you might break things. If you end up adding extra categories on the first sheet, you'll have to also add it in on the Category Totals column. From J2 to J31 it's coded to sum the totals that match the category in the I column, so all you have to do is select your new categories from the drop-down from I16 to I31.