Originally posted by Dom:
In my experience, eco-renovation is a balance between the specific needs of you and your building, the building regulations, listed building status (if any), knowledge of available products, personal skills or availability of trades, timescales - and of course cost!
It's a daunting rite of passage to build up sufficent knowledge and skills to confidently specify (or carry out) the choices that are best for you and your building - and particularly to reject inappropriate or "sales based" advice.
I found the Society for the Protection of Ancient Buildings (http://www.spab.org.uk/) was a good all-round source. Conservation and eco-renovation share a lot of common ground. They're also pragmatic about real-world budgets and the balance between practicality and cost/conservation.
We like SPAB - added to the list - thanks Dom 
Any chance of asking them to provide a speaker?
Also useful is a personal network of people travelling the same road (don't be shy of knocking on strangers doors of well executed projects too).
Some very short (10-15 minute?) members presentations would do a lot for networking.
We'll have this in some shape or form