I just ordered a couple from Amazon (after flipping through them at my local 'brick & mortar' book store): The that I picked out were:
PSE4 for Digital Photographers by Scott Kelby -- his books have been getting rave reviews from the digiscrap community for some time now
PSE4 -- The Missing Manual -- from the O'Reilly folks, who write those nifty books for programmers

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Lisa, Mom to Nora & Lily
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