Where can you get the accordion for Garageband for free? There aren't a lot of options available, but you can access one.
Connecting a condenser microphone to your computer is done through an audio interface with phantom power, or via USB cable if you're using a USB Condenser Mic
Connecting a dynamic microphone to a computer is a straightforward process. You just need a couple pieces of gear.
Exporting MIDI from Garageband, while not technically possible, can be done with an .aif to MIDI converter. Read this article to learn more.
EQing a nylon string guitar isn't all that different from a regular steel-string acoustic, but there are some differences.
Pitching your vocals in Garageband is fairly easy to do, and it can be accomplished in a couple different ways.