As FRA-Runway mentioned, there is the BA 744 that arrives daily. It also comes back from San Diego at night and leaves Phoenix at 9:50pm. As for other 747s, Phoenix leaves a lot to be desired. Northwest was bringing in a 747-100/200 in at the end of 1998, but I think that has ceased since I didn't find it on their website. They do use a DC-10; if you're interested in that, check their website.
As for other 747s, you'll rarely see them in for service at Aviation Management Systems (what used to be the Sabre Tech hanger). Occasionally cargo airlines will fly them in (usually Polar Air or Atlas). When I was there in August, I happened to spot a MK Airlines Cargo 747 (9G-MKI)--that was a rarity. Other than these, you may see Delta, United and FefEx widebodies, although those aren't really Jumbos.
Basically, what I'm getting at is that most Jumbo traffic at PHX is unscheduled and you have to stay there all day to catch the interesting stuff.