Two good books that spring to mind are:
- Modern C++ Design / Andrei Alexandrescu (It's actually 7 years old despite the name!)
- C++ Templates: The Complete Guide / Vandevoorde & Josuttis
It's quite an in-depth field, so a good book like one of these is definitely recommended over websites. Some of the more advanced techniques will have you studying the code for some time to figure out how they work!
