I tried my Air Horn but the guy in the truck still proceded to backup onto the road. I ended up hitting the breaks. They guy backed all the way out and I stayed where I was. I asked him if he heard my horn and he said, "no" and then "I'm sorry". I just told him "no biggie" and we parted ways. I wanted to tell him that he should pay more attention to cyclists...however I didn't think it was necessary since there are a whole new load of "Share the Road" type signs with Bikes painted on them. I have found most motorists when confronted to be "okay" they don't get mad or angry at me.. Just be prepared for the worst and don't assume they see or hear you.
Keep Cycling,
Jeff