Here is a link to my deals spreadsheet for the week. This is how I plan for the upcoming deals, and make a game plan before I head out to the store. I try to calculate any out of pocket expenses ahead of time, so I can minimize hassle in the store, and maximize savings.
I keep a spreadsheet for each week as deals appear--this way I don't waste time searching for deals that I may have read about weeks before, and I can prepare for upcoming sales by trading for q's, sorting my own stash, or arranging a special order for a particular deal (so that I wouldn't clear the shelves for other customers) I have yet to plan far enough in advance to ever do a special order--but I want to be prepared for the possibility if the right deal comes along (free TP or something ;) )
Each store has a tab in the spreadsheet, then I print it out and take it with me when I shop. I usually leave it open on the desktop for DH while I'm out shopping--in case the quantity or price differs from my plan--he can change my spreadsheet data more quickly than I can pen/paper it!