Dean Allemang and Jim Hendler's book provides a good overview of data modeling for the Semantic Web. Amazon purchase link: Semantic Web for the Working Ontologist: Effective Modeling in RDFS and OWL. As someone who has invested a lot of time with both open source tools (Jena, Redland, Sesame, OwlApi, Protege, and Swi-Prologs Semantic Web libraries) and a commercial product (Franz AllegroGraph) it is refreshing to read a good book that abstracts away details like specific tools and RDF XML serialization and covers concepts and modeling how-to issues. I found it useful to enjoy this book at a high level while stopping occasionally to pause and experiment at the low level with OwlAPI, Redland, Protege, Sesame, and AllegroGraph. BTW, I wish that someone had told me years ago to never view XML serialization of RDF :-) The authors choice of showing XML serialization one time and then using N3 is very good.
There are a few tiny annoyances with this book, the primary one being small errors in the text that should have been caught in technical review. These do not however detract at all from the usefulness of the book - it is just too bad that such a very well thought out book has easily fixed mistakes.
For me one of the potential uses of this book is to loan it to or recommend it to customers who might want or need to use Semantic Web technology: I make my living as a consultant and it is important to have well informed customers and this book will provide a good understanding and rational for technically inclined customers, especially people with strong domain knowledge who want to (and can) directly participate in modeling efforts.