Photo Tidbits has just published a detailed guide to creating infrared photos with your digital camera - apparently this is a technique best suited to cheaper digicams (found via StillJournal):

“Ironically, digital SLRs (except for the E-10/E-20 by Olympus) do not allow you to use the LCD monitor for picture preview and composition. You have to compose without the filter (using a tripod, of course), then put the filter on and shoot blind. If you have a digital SLR and intend working in infrared, you will be better off getting an inexpensive non-SLR model specifically for infrared. You need a small backup camera anyway.”

Website: Photo Tidbits - Infrared Photography With a Digital Camera