Like many of you, charts is an essential part of any business presentation and like many of you, excel is our best friend (and worst enemy). The process of data visualisation I've learn't is a new skill set, and not an easy one for a subject that can be quite complicated. Finance has many variations, as with many other types of charts; some data is combined, some require custom charts and so on.
Here are a few interesting blogs that I've found useful for choosing the right chart for the right data, chart design and formatting and some data visualisation ideas.
Excel Charts – good examples and tutorials using excel.
Junk Charts - Deconstruction and reconstruction of questionable viz.
Visual Business Intelligence - From popular B.I. guy, Stephen Few.
Chart Porn – never mind the name, a good site for charts.