I found this book
made very interesting reading. He has a lot to say about the effect of the room and it's layout/furnishing
Thanks for the heads up Visionary, that looks interesting, I've ordered myself a copy!
To echo the comments made above, I agree that, from what I have read, treating the room adds far more value than virtually any other upgrade. My own voyage of discovery with room treatments will begin next year when I get to have a dedicated room at long last (after 10 years of dreaming of one!).
Given how effective room treatments appear to be, not only on an absolute basis, but in terms of bang for buck, it amazes me how frequently they are overlooked. Perhaps similar issues apply to others as they do to myself in that they wouldn't pass the WAF for a dual purpose room, but even so I frequently see dedicated rooms with no treatment at all.
I have also found these books worth while reads (if a little technical):
The latter is frequently quoted as being the bible for acoustic design of listening rooms, but as I have said its possibly not for those looking for a Dummies Guide.
Finally @ VoodooDoctor - that is a great looking room and great to see someone who has fully utilised proper acoustic treatments.