Adobe Audition is my choice for editing podcasts and other audio. At NAB Show Adobe demonstrated the new "Essential Sound" panel.
Adobe Audition's Sound Removal Tools to the Rescue! There are some nifty post production tricks in Adobe's lineup of programs that could save you hours upon hours of time with just a few clicks. From No Film School.
How to Use Adobe Audition. While various versions are available with a few differences and new options, Adobe Audition is one of the industry standards for audio file editing and creation.