Hoefler + Frere-Jones, a type foundry, has a site full of elegant faces and information. Look at The Proteus Project and Gotham as beautiful moments, but their entire list deserves a readthrough. In fact, I heard them speaking on npr -- they were speaking about Gotham, the elegant font used in the Obama campaign -- and I realized how much they care about the invisibility of their craft. They want typography to be a support system, unnoticeable because it does it's job so well to help the reader and convey info. Lovely.
Their Troubleshooting and Info Guide in ASK H+F-J is full of good info (the OpenType post, as example).