My advice:
1) invest in a good
thick sheepskin for sitting on. It helps prevent "monkey-butt"- the prickly heat rash you WILL get otherwise. No fun riding on an itchy butt! The thicker teh wool/fur, the better!
2) invest in a very good air mattress or inflatable bed. The smallest pebble feels HUGE under your back after riding for 10 hours.
3) take a cooler with you and keep bottled water in it. The club did Sturgis in 2003, and I had my old cooler "Big Red" strapped onto the passenger seat the whole trip. Everyone stayed hydrated and that is very important - we had temps around 100F, and you will get at least that when you get near LA
4) <chuckle> be sure to take lots of wooden stakes - Los Angeles is full of vampires! Just watch some reruns of Angel - you'll see!
I'd also advise investing or building a handlebar mount for your camera. But it depends on how you like to travel- stopping to take pics or taking pics/videos while travelling....
And have fun!