GarageBand and FL studio (Fruityloops) are similar programs both designed primarily for loop based music production. They can be used for live instrument multi-track recording.
GarageBand is part of the Mac O/S while FL Studio needs to be purchased.
Another similar program is Mixcraft. Can be used for loop based work or multi-track recording of live instruments. Also needs to be purchased.
A free alternative is Audacity. A multi-track audio recording and editing program. It does not support loops but is designed for live recording.
It's worth a try and might be all you need.
http://audacity.sourceforge.net/
http://www.acoustica.com/mixcraft/
Another more professional application to consider is Pro Tools.
Worth a look. Depends on how far you want to go.
http://www.digidesign.com/