You go Dan! ATM'ers who grind their own mirrors are a dying breed, so it is great to see someone wanting to have a go!
If you want supplies, you might try Matthew Lovell via
http://www.telescopes-astronomy.com.au
I increased two shirt sizes across the shoulders when I ground a 10" mirror, so it will be interesting to see what happens if you do a 30"!!!
All the best,
Dean