It's not easy to follow as Neduro says. I was there this year on the Peru portion with my Adventure Moto Tour company. It is crazy, traffic, few directions, and miles of desert sand to cross to try to see anything of the race...
I will be back in 2014. Maybe w'ell meet up!
Trouble is too that it should be running south to north this time. So you will have to go all the way south, then follow it back north!