Welcome to the hobby Graham, Joel and Rod,
Sounds like you all had a ball of an introduction!! Good advice Duncan, a right angle finder will really assist.
A Telrad is also a great investment. It looks a bit odd when you look at it, but sooo easy to use.
Graham, I don't know if you need to go as low as a 6mm. Like Norm suggested, I'd stick with something around the 8-12 range. More magnification does not always translate into bigger and better images. Conditions have to be pretty good for something that low to work.
Graham and Joel, you've scored a perfect 'first telescope' in my opinion and I'm sure most here will agree. Now it's time soon to learn some starhopping techniques.
Good luck to you all and keep the questions coming.
hoo roo,
Stephen