Audacity - Fabulous free audio recording/editing software, simply the best!
Copyright Free Music - Purchase copyright-free music for your Podcast intro and fadeout at $.99/track
Feed Validator - Troubleshhot your feed for free
FTP for free- Best ftp client avvailable, 100 % free, for upoloading files- Coreftp
HTML editor - Free and great for xml feeds - Coffee Cup HTML Editor
The best microphone for Podcasting is the fabulous, plug-and-play USB Blue Snowball. These show up on eBay often, so check there first.
Do you dream of being a talking head? Then video is for you, and I highly recommend Sony Vegas video creation software. Check eBay for 2nd hand copies.
No or limited webspace on which to host your Podcasts? No desire to create and maintain your own feed? No problem--check out Podiobooks.com, a wonderful alternative for Podcasters!
Video & audio file conversion--a seemingly endless task! Find some great free video conversion tools here, including the essential Freez iPod Video (M4P) Converter, at SmallVideo.
If you are interested in self-publishing as well: Publishing Resouces