Exploring InDesign CS4, by Terry Rydberg (Delmar Cengage Learning, 2009)
A wonderful textbook to teach yourself (or someone else) how to be productive and creative in InDesign. In addition to teaching software techniques, Terry Rydberg weaves in design advice, production knowledge, and subtle hints to do things the right way.
InDesign Type: Professional Typography with Adobe InDesign CS2, by Nigel French (Adobe Press, 2006)
Real World Adobe InDesign CS4, by Olav Martin Kvern and David Blatner (Peachpit Press, 2009)
InDesign CS4 for Macintosh and Windows: Visual QuickStart Guide, by Sandee Cohen (Peachpit Press, 2008)
Adobe InDesign CS4 One-on-One, by Deke McClelland and David Futato (Deke Press, 2008)