Tempe Diablo Stadium opened in 1969, but the Los Angels Angels didn't start making full use of the facility until 1992. This is a nice ballpark, but the best time to get to the park is early. Why? Because parking becomes crazy the later you arrive.
It's a great park to attend if you want to watch the team work out and get some pictures and autographs with your faves. The players walk along from the stadium to the huge practice field and vice-versa and anywhere between there is easy access for autograph seeking. Word of warning: Manager Mike Scioscia requests the fans walk along with him as he's going from one place to another. This doesn't bode well because people run to catch him and more times often than not someone gets hurt. Other than this, it's a pretty decent area to hang until the players trek back into the stadium for drills on the field.
Their team shop for souvenirs is a bit small and gets crowded fast. I found a good bargain in there the day I went and came away with an ANGELS visor for $6.50, which I got autographs on that same day, so not a bad souvenir to pick up to support the team.
The guest services people at the stadium are really helpful and friendly so don't hesitate to ask them anything you may need or are looking for.