We had that problem when we switched to Tru energy too....

I first rang them after about 6 months of no bill and they said they were having some sort of 'billing problem' but it should be fixed soon and they would send a bill ASAP. From memory I think they told me to ring back in a few weeks if I hadn't received anything. I remembered about 2 months later and rang again and they said they were still having a problem. From memory I think we didn't get the bill until over a year after we connected with them however, I did learn one important thing they can't charge you for power used over a year ago so if they don't send one soon it might be worth not ringing, I mean, you've tried to do your best and the honest thing. Once it's over 12 months they can only charge you for the immediately previous 12 months and no more