Hello Mike,
And welcome to Apple Discussions!
First of all, as you guessed, there is no way to directly delete the content from your iPod.
As for the podcasts, are you sure that none of them are under the
Music section of your iPod? Where did you find the first 3? From under the "Podcasts" tab for your iPod in iTunes?
Here is another article on how to delete songs and such from your iPod if need be.
http://support.apple.com/kb/HT1855
Let me know. Would love to help. 😉
B-rock