I\'d like to create a simple Swing app. I\'ve got very, very, very little experience with Swing, however. I want to create a one window app that refreshes every 5 minutes
On top of the resources mentioned by @Zach L (particularly regarding the timers), I would take a good look at Seesaw, especially since you're writing this in Clojure.
In particular, I note the seesaw.timer for firing the refresh events. Using a JTextPane (read-only) or a JEditorPane (editable) would work well for displaying richly formatted results (like HTML).