I try to do a long ride in the 5 hour range every two weeks. I ride over three hours at least 3 days a week. wednesdays are off, mondays and fridays are easy, <2 hours.
On the days of long rides, I generally get up late, eat a lot at brunch, pack a couple of clif bars and a banana and just go. I generally try to keep the pace low for the first half hour, then I just go meduim for the rest of it. I really need a HRM, though, I want to try to keep my HR in the 60-70% range for the long rides. Base, you know.