Also being from the UK I was amazed at some of the prices of UK £1 coins advertised in the USA; we have them floating around in our pockets and I don't think there are any really rare low mintage ones.
Perhaps I should rake through my pockets and advertise them on ebay.com, LOL.
I usually notice them in change towards the end of the year for that year date, or at the beginning of the next year. Indeed when they first come out they are in uncirculated condition, some could almost be described as mint. I sometimes put away a nice design myself.
Here's a useful page illustrating the different designs for the different years...http://www.royalmint.com/discover/u...e-pound-coin
Beware of fakes; they reckon around 3% of all £1 coins in circulation (around 43 million) are fakes; some are getting incredibly difficult to recognise due to the increasing skills of the counterfeiters and the banks basically ignore fakes and they go unrecognised through the system; most can't be bothered to sort them out.