Dirk's Tiny Podcast

Not all software is created equal. Here is my little list of audio tools I've seen in the space and my recommendations:

• Audacity - open source, huge community, free, available almost everywhere. That is the reason why so many people recommend it. The downsides are: destructive editing, clunky UI, some functions it offers do more harm than good. So in summary: it does the job but I do not recommend...
• Garageband - free or low cost in the Apple ecosystem, quite capable as an editing tool.
• Hindenburg Journalist [Pro] - The regular version of Hindenburg is everything most podcasters need and you'll be hard pressed to find a tool that is more comfortable and powerful as a podcast production suite than this. It is optimized for talk radio which in itself is a differentiator from all the other tools out there. The pro version is rather pricey but worth it if you know you'll need the features it offers. 
• Reaper - this is the tool I use (with an extension, see next point in the list). I'ts created by the same folks that gave us WinAmp back in the day and it is short of amazing value (as in very reasonably priced but complete in features and quality). Reaper is a x-plattform, batteries-included audio editing platform that may be a little too complex and powerful for the average podcast producer at first, but it can be extended and themed which is what a podcast extension called "Ultraschall" does (see below).
• Ultraschall.fm - this is the landing page of the reaper extension called Ultraschall. It turns your complex reaper installation (that is optimized for music) into a slick and clean podcast production suite. It is open source and free, But please be warned: Behind the project is a German community of enthusiasts who do that for free in their spare time. They are not necessarily equipped to give you extensive support or answer feature requests. 
• Ferrite - a tool for mobile audio production
• Adobe Audition - well, Adobe :-) 
• Pro Tools