Prinz’ paper takes a rather familiar form: he discusses arguments for a particular view of emotions and then a series of objections to this view, in each case suggesting the sort of reply to the objection that might be possible. Prinz presents the issues raised clearly enough that I will only suggest a few things to bear in mind as he leads you through them.
• The theory Prinz considers—the “James-Lange” theory—is quite different from Solomon’s approach to emotions. So, although ideas like Solomon’s appear in Prinz most directly as just one of many objections to the James-Lange theory (and this theory is only alluded to in Solomon), it would be fair to regard those two views as opposing poles.
• Prinz will suggest modifications of the James-Lange view as he considers objections to it, and it's worth noting these suggestions as he makes them since he does not really pull them all together at the end. He does discuss the modified theory in his final section, but he tends to assume there that you already have in mind its general form.
• William James was as much a philosopher as a psychologist (Lange was a Danish physician who suggested similar ideas independently). The people Prinz refers to are a mixture of philosophers and psychologists, but it won’t always be clear who is which from what he says about them. You can get a little better sense of this by looking at the entries in his bibliography; but, in case that doesn’t make it clear, let me note that both Domasio and Lazarus, who are near opposite ends of the spectrum of views, are among the psychologists Prinz mentions.