I got mine from my dealer but there was a thread recently about Haynes coming out with one. I might buy one myself... maybe it will have a bit of diagnostics in it.
If you can manage it, best to get both. The Haynes manuals I've had for other vehicles have great pictures (which the factory manual doesn't) but they are a bit dodgy with specifications and such.
Let's hope there's intelligent life somewhere in space 'cause it's buggar all down here. -- Monte Python