Tim Dexter runs an excellent blog here. It contains great content on BI Publisher, and if you have questions on BI Publisher, or think you have questions on BI Publisher, then that's the place to go. Of course, you don't have to, you can stay here on this blog too... but I am trying to be helpful here.
In case you want to catch up on the latest and greatest new features in the 10.1.3.3 release of BI Publisher, while you can always download the software from OTN, or go to the OTN page here, you should also bookmark or subscribe to the BIP blog's RSS feed.