Hey Dave,
I don't know any "how to" books, hopefully others will chime in with suggestions. Lightroom is more like Picasa or iPhoto than Photoshop. It's designed to browse through and do quick fixes to large batches of photos.
To get you oriented a little, along the top of your screen you'll see a big "Library", "Develop", "Slideshow", "Print", "Web" links - these are the Lightroom modes. I mostly use Library and Develop:
In library mode, it's easy to browse your photo collection, group photos together, and set up publishing exports with popular web services or hard drive folders.
In develop mode you can still navigate between pictures in the current collection, but it exposes a slew of edit controls for cropping, adjusting exposure/color, toning, detail (this is where the AMAZING noise reduction settings are), etc. Unlike Photoshop, all of these edits are non-destructive (your original photo is never over-written). Instead, you must export or publish the photos.
One final thing, if your camera supports a RAW mode, use it. The RAW images usually have more dynamic range than JPG and Lightroom will let you access details in your photos that are lost in JPG.
Have fun!
--Shawn