Here’s a terrific resource for free embroidery patterns, along with some tutorial information on cleaning up scanned patterns. I think you’ll find these patterns super-useful for all kinds of embroidery techniques – either to use as they are, or to use a source of inspiration for adapting.
The website is actually named after an old embroidery stamping catalog, the J. F. Ingalls pattern catalog from 1886.
Update: May, 2013: the original website for this article is no longer available. Instead, visit this collection of the J. F. Ingalls pattern catalog images on Flickr.