Normally, if you click the "Podcast Directory" link at the bottom of your Podcasts pane, the screen changes and takes you to the iTunes Music Store's Podcast Directory. If you click "Subscribe" to add a podcast, iTunes dutifully takes you right back to your podcasts list.
But what if you don't want to go back? Sometimes I want to subscribe to several podcasts I see at once, like a half-dozen NPR shows I want. On slow computers or connections, it can be frustrating. Here's how to quickly manage this:
Double-click the Podcasts category, in the leftmost pane of iTunes. That opens the Podcasts list in a separate window.
Now, if you click that link to the "Podcast Directory," your Podcasts, in their separate window, remain open. The main iTunes window will come forward and show you the iTMS. While you're there, you can click Subscribe, and the Podcast window updates (and comes forward), but the iTMS window remains back there, unchanged. If you have room to spread them out (two monitors are great for this), you won't even have to deal with the windows popping over each other.
Keep clicking to subscribe to more; both windows remain open until you decide to close them.
Mac OS X Hints
http://hints.macworld.com/article.php?story=20060602154836229