I found a really simple seeming website with a step by step tutorial. http://www.how-to-podcast-tutorial.com/00-podcast-tutorial-four-ps.htm I also found "CamStudio" which is a free download that would facilitate them. I do suggest if you use CamStudio to review several of the tutorials on TeacherTube/YouTube. They really helped me with the fine tuning of using the program.
I just completed my first ever podcast (thank you very much) so I know where you're coming from. I used Audacity to record it - it's a free download - www.audacity.com. There's this link as a tutorial and a YouTube tutorial and although we didn't do a podcast on public service announcements, I found this Read Write Think plan very useful in helping me guide my students through the process.
Funny podcast story. My co-teacher and I spent a year discussing podcasts and doing them with our students. We decided we had the perfect project, each kid was to do a podcast as a passenger or crew member of the Titanic. We still didn't have a clue how to do it but we had our tech guy download Audacity. We were so busy with other components of the project and I yelled across the room at two students "Carolina and Chloe, figure out how to do a podcast." Five minutes later I heard "Mrs. B we're done, do you want us to know how to edit?" I laughed--give it over to the kids, they'll figure it out!!
My students did still-frame podcasts earlier this year and are currently working on creating video podcasts where they are actually going to make an argument for why we should be adopting the use of several different Web 2.0 tools in our classroom. Podcasts are not terribly difficult, but you should expect there to be some learnign curves as you move forward.
I'll try to pull some material together and post it here.
I've used audacity as well, with success. My suggestion for creating very quick on-the-go podcasts is to get a Belkin Recorder to plug into the bottom of an ipod. It essentially turns the ipod into a recording device and any recordings are turned into voicememos that can then be imported into itunes. Another option is to request a google voice number, and when the number is called, the message is stored in an inbox. Each message has an embed code, and the "podcast" can then be embedded in a blog.