One more enthusiastic vote for the two books already recommended: AppleScript 1-2-3 and AppleScript: The Definitive Guide.
Also, save yourself a lot of frustration and buy a Script Debugger license. I learned that far too late in life.
You don’t have to pay that amount. Since version 7 they introduced a light version you can use for free. Although several features are disabled it is still many times better than the standard Script Editor. To be able to see the values of the variables after execution of the script is indispensable.
Thanks for the advice. Based on the enthusiastic endorsement I purchased Neuburg’s book, and downloaded Script Debugger. For now I’ll use the free version, but if I get into it heavily I’ll upgrade to the paid version. I’ve also bookmarked the MacScripter site, I’m sure it will be helpful as I begin learning.