I got the new book from Matt Lombard last week, "SolidWorks Surfacing and Complex Shape Modeling Bible". I'd highly recommend it.
I've been a casual SW user for a year or so, and am getting more serious about using it for product design now. I don't have any experience developing with surfaces directly, this book breaks it down nicely so that you can develop a good workflow for analyzing a part and modeling it.
Amazon.com has it of course.
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