You're probably not surprised to hear that angels are all over the Bible. They may stand behind the curtain at times, but they're dynamic, powerful characters who help God and sit in his divine court. Just remember that heavenly beings and angels aren't winged cherubs yet. They're a big deal, but they haven't quite gotten the Miltonic treatment.
Satan and pals are really only around in the frame story. God does mention them in his speech at the end, but at that point, they only really sing his praises. In the frame story, on the other hand, the angels are kind of like members of the divine office. They go to meetings with God, interact with him, and even challenge him—Satan, we're looking at you.
You might remember that Eliphaz compares angels to humans. He basically says that if angels aren't perfect—which they aren't—there's no way humans are. So wait, we're comparing humans to divine beings? Yep. In fact, Satan himself tells God twice that he spends his time hanging out on the earth, "walking up and down on it" (1:7). And God definitely joins in on the human banter, too.
If you're thinking this is a bit strange, you're right. In fact, it's not like this anywhere else in the bible, really—we dare you to find another spot in the Bible where God and his posse seem so human.
All of that human-like stuff went down in the prose section. But in Elihu's speech—right smack dab in the middle of the poetry—we hear that that angels can act as guardians for the righteous (33:23-24). Doesn't that imply that angels are better than humans? So which is it? Is their power designed for the good of the righteous, or are they around to make wagers with God?
Watch out, folks. These combinations of ideas from different eras can get a bit dicey.
[Other places where angels are mentioned include 1:6, 2:1, 4:18, 15:8, 15:15, 38:7, and 41:9. Check 'em out for yourself.]