I found Martin Evening's book way too encylopedic. I found the
Photoshop Lightroom 2 For Dummies (For Dummies (Computer/Tech)) by Rob Sylvan (Paperback - Sep 9, 2''8)
and
The Photoshop Lightroom Workbook: Workflow not Workslow in Lightroom 2 by Seth Resnick and Jamie Spritzer (Paperback - Oct 31, 2''8)
to be my favorites for overall readability while also being in depth. If you're looking for reviews, amazon is an excellent source. Reviewers are average readers who care enough to make comments on their reading. I have found them very helpful on many occasions when trying to decide which book is best for me.
NJHeart2Heart Dawn