Maria Korolov has a post up on Hypergrid Business titled: One-Question eBook Survey. It looks like Maria is planning to publish a couple of eBooks that deal with setting up an OpenSim grid and another on using OpenSim grids.
If you have an interest in OpenSim, click over and place your vote for which you think is a more important and useful book.
I will also point out that OpenSim is a great place for having a test sim. The SL Preview Grid is great for last minute testing just before uploading into Second Life™. For most of us the areas of the SL Preview grid we can use have short ‘return times.’ For some testing that can be a serious limitation. Having a region in an OpenSim grid can give one a permanent base for long term testing. Running a grid on your personal computer is basically free.