Where can you download applications for MacOS 9?

Both MacUpdate and VersionTracker maintain searchable directories of MacOS 9/Classic software available for download.

What software is available to manage and play MP3s in MacOS 9?

The simplest answer is to use an older version of iTunes, which is based on an earlier program called Sound Jam. iTunes 2.0.4 is the last version available for MacOS 9. Although iTunes 2 lacks some of the features of later versions, it has the basic capabilities that you need to rip and burn music CDs and store a collection of music in MP3 format.

However, there are two other MP3 software programs that you may like more than iTunes 2 -- Melonsoft's Cabrio 1.4.6 and Panic's Audion 3. Both are freeware and are available for MacOS 9 as well as MacOS X.

Melonsoft notes that Cabrio "was engineered to take up virtually no screen space or system resources. . . [and] combines ease-of-use, stylish design, power and performance into one small application."

Panic allows Audion 3 to introduce itself, saying:

Hi! I'm a single app that bravely handles all your audio needs - I'm easy to use, but with gobs of advanced features ready to be discovered! I can play your Audio CDs, your MP3s, and your streaming network audio, I can encode, edit, mix, sort and manage, visualize and hypnotize. And now that I'm 3, I can broadcast, record, crossfade, and even hang with your [now vintage] iPod. Best of all, I've got that Panic design - light, simple, and powerful. It's sure nice to meet you! Go on, download me!

Audion 3 has a number of features that were not added to iTunes until versions later and some features that even the latest version of iTunes for MacOS X still does not offer.

Screenshot Credit: Panic Software

Those interested in the most full featured MP3 software for MacOS 9 probably would be happiest with Audion 3. MacOS X users likewise might still be interested in some of the features of the discontinued program. However, as iTunes, Cabrio, and Audion all are free, you can always download each program and keep the one you like best.