this will show you how to make Itunes smart playlists for podcasts and music so you can have every episode of certain podcasts, and the latest episodes of the others. Its also good for music – eg songs you have never played, songs you havent played in the last 6 months, etc.
now you have lots of options. if your podcaster fills out the artist info the same for each episode, then use that, eg
you might have to play around to get the right options to get your specific podcast.
make one smart playlist for each podcast you want to have lots of episodes of.
under the podcast sync tab
this way you will have every episode of your selected podcast, and only the 3 most recent (or whatever you selected) of the others. and they are automaticly updated every time you get new podcasts
I also made a couple of music related smart playlists
I also added a couple of static playlists with albums I like having at all times and made sure I synced them to my iphone. that way I always have new music, tracks I have never listened to, tracks I havent listened to in a long time and the music I listen to all the time, and I always have new podcasts, and podcasts I like listening to a lot (like the jund dubstep podcast =)
the good thing about these playlists is that every time you listen to music on your iphone or your mac the playlists change =)
Sources: Apple Support