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ImageWell is very good. Just drag and drop image files (not RAWs) and it outputs resized images. If you don't have many files to do then the shareware version is probably fine. If you need to actually do batches, then the registered version will do that for just $15 bucks.
 
Why can't you just resize one photo in photoshop, make an action then use the action on a batch?
 
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