I can recommend Joe's book (I bought the pdf). He has an endearing self-depreciating tone, despite being Erlang's (key) developer. He also sprinkles in the actual reason for certain features.

I'd also recommend Joe's "A History of Erlang" (free pdf) for the why's of it (which is my main interest): http://www.cs.chalmers.se/Cs/Grundutb/Kurser/ppxt/HT2007/gen...

I will second your recommendation of Programming Erlang: Software for a Concurrent World. It's quite good.

Great compilation. I have started looking at erlang and this would really help me a lot.

Erlang sounds really interesting! Great compilation of resources.