Yesterday, Dadinck made a comment that showed me a faster way to enter numbers, by using the alt key on the keyboard instead of hitting the sym key and using the tedious symbol selector. He also pointed me to a good site for Kindle tips. Thanks!
Meanwhile, I discovered that Amazon has a PDF conversion service, which will let me email PDFs to it, convert them to AZW files for the Kindle, and push them to the Kindle through WiFi (it emails them back to me, as well). The pretty formatting is lost in the process, but it retains any images, and for almost all the PDFs I want to read the result is just what I need. Having them converted to Kindle format means that I control their display as text files and the text reflows as I change the font size, so the zooming problems go away.
I also found the troves of free books, and, despite my intent not to load the device up with books, I did snag a few of the free ones — about a dozen — including such wonders as Alice’s Adventures in Wonderland and Through the Looking-Glass, and what Alice Found There, James Joyce’s Dubliners, P.G. Wodehouses’s Jeeves books, and Doyle’s Sherlock Holmes stories.
OK, maybe I’ll keep it.