You've been meaning to get round to it for years haven't you? Did you realise that there are some brilliant training courses online that can help. A much underadvertised resource IMHO is the office online training. It takes you through the lesson with audio narration and flash demos, then there is a practice file to work through - like homework. It has an example spreadsheet that it opens for you and a set of instructions in another window to work through. Most of the courses are 30 minutes or so - easy to fit in to your day. Why not take one lunch hour a week to improve the way you use Office tools?
Case in point about using Excel better: how to add a calculated field in a pivot table?
Easy. Click in your pivot table and on the pivot table tab, click formulas, calculated field. Create a formula using the fields of the pivot and it adds it in as an extra column. Easy. What most people try and do is create a formula outside the table and this gets messy when you cant address pivot fields and the formula won't copy down a column etc.
So a little bit of study pays off..