Finally managed to obtain an o2 nano sim after many hours of conflicting information and excuses from local stores. I heard everything from "We won't have them until launch day" to "We only get deliveries on Wednesdays". I called my local store again at 3pm and asked the same mundane question, expecting the same result. To my shock they said "Yes, we do". After confirming they were nano sim and not micro, I headed down to the store. 10 minutes later I was transfered over to the new sim by an o2 member and walked out a satisfied customer. There is light at the end of the tunnel... Just don't give up.
The good news now, I'm officially ready for the iPhone 5. Bring it on!