If you think a shady garden is a liability there is a good book that will change your mind. Gardening in the Shade (Horticulture Books, 2004) was compiled from articles that originally appeared in Horticulture Magazine. The book is divided into four sections: techniques, general design, plant for shade and step by step projects. Some of the plants suggested are Epimedium, sedge, Cyclamen and Japanese Spicebush (Lindera obtusiloba). Any one with cedar trees in their garden will want to read the essay by a local Northwest writer on coping with dry shade.
Other resources for shade gardening include the classic book, The Complete Shade Gardener by George Schenk (Timber Press, 1984) and the web page created by University of Missouri Extension.