Frequently Asked Questions about spinning wheels
FiberArt webring
How to make a drop spindle
How to use a drop spindle
Online videos of how to spin yarn with a drop spindle
Tools and Tips for weaving and spinning
AllFiberArts (formerly About.com's Weaving and Spinning site)
Spin2Knit, the site for fiber aficionados
The Hatchtown Farm has got a lot of good information on fiber and drop spindles, among other things
FiberArt.com is "dedicated to the promotion and continued growth of the Fiber Arts." There are a lot of software links, a calendar of fiber-related events, extensive lists of guilds and organizations, and a cute sheep animation
The Spindlitis page is dedicated to drop spindles--making them, caring for them, using them, and so on. There are terrific photos and reviews of all sorts of drop spindles here. There is also a Spindlitis e-mail list