I am going through the same exercise here in Europe, except the Authorities here are somewhat more anal about towbar ratings and stuff about dynamic testing etc etc.
Anyway, I have looked high and low for photos of a 1200GT SE with a towbar or hitch fitted, but have not found any. I have a supplier in Holland telling me he has them in stock, but no photos of it mounted on the GT. There is one for the LT, and I have to say it looks god-awful. The Dauntless hitch looks ok, but expensive.
Now having said that, there is a new mono wheel development in England. Check it out here
but alas they have not yet developed a hitch for the GT. From what I hear, it seems to be a problem to get an approval from the Manufacturer (BMW) that it is ok to bolt on a hitch. From what I can gather, basically has nothing to do with safety, it is all about Liability if it all goes wrong. And since it seems that BMW has still not sorted the FD issue, I can't for 1 minute imagine that they will willingly sign off on something that will create added stress to the FD, i.e. pulling 150-250kgs.
is another resource and discussion.
is a guy that calls a spade a spade, but a lot of info. There was another dude on some other website (can't find it anymore) that basically was saying that if he doesn't stock it, it ain't made, and it never will be, so don't bother to ring me if it ain't listed.
is the trailer I am looking at, because it will also fit nicely behind my Smart.
Hope this helps.