I'm amazed this is your first time in 5000 miles, I got one by the second week of cycling to work.
Interestingly I spoke to the guy who work at a local bike shop and he says he doesn't get much trouble but then he's 6 foot 4 and very heavily built and I'm 5'9 and built like Vincenzo Nibali.
I think in the last year, I've had only three instances of drivers sounded their horns or shouting at me. In the other occasions, they've done this from a distance though and not deliberately pulled across my path (today was clearly deliberate, rather than poor driving, as he left what would be considered the normal lane in order to do it).
Obviously I have experienced the odd poor driving, and people getting close because they are poor drivers (or I assume). In only my 3rd or 4th ride, just before that same roundabout, I had a car undertake me on a right hand turn out of a one way road. I remember posting about it. In that case I just believed it was poor driving, it's a wide road, enough for two cars, and the car turned right in a turn left position, in order to squeeze by me, effectively putting me in the middle of the road on her offside.
I think I get more drivers go mad at me when I'm in my car, because I like to obey box junctions and keep clear signs.