I've done an overview/walkthrough of the new OpenOffice.org charting tool that will be released with version 2.3. It's a procedural approach, so to supplement it here's a PDF reference to some of the more complicated windows. I'll be including it and similar information in an update of my workbooks and Guidebook as soon as 2.3 has been released, and I'll provide the update to the book in PDF form, as well, so those of you who've already purchased the Guidebook can have the new chart info.
A note on the new chart tool -- in this window, you can specify multiple noncontiguous ranges. However, sometimes especially when they're in another sheet, they don't seem to take. Might just be a bug not worked out yet.
So for now, to more reliably add noncontiguous sections, just skip that window in the wizard, click next, and use this window. Click Add, then you'll get an item called Unnamed Series for which you can set the range of cells for the name (label/heading), the categories (must be the same as all other data series) and the Y values.