Not sure if Quickbooks is on the installer disk of panther but if you are sure..: get yourself TinkerTool to unhide system folders. Insert your panther disk and look for a hidden folder (.foldername). I forgot the name of that folder, but there ain't so many hidden folders on the panther disk. There you should find many image files and one might be Quickbooks. Good luck!
To my knowledge QuickBooks has never been bundled with any Mac. However, from time to time, Quicken has been included with various Mac models -- generally the consumer models (eMac, iMac, iBook). If Quicken was bundled with your Mac, and you bought the Mac new, it would have come pre-installed in the /Applications folder. If you had it and erased the drive or deleted the application you would find it on the Software Restore CD/DVD and not the OS X or OS 9 install CD/DVD.
FYI QuickBooks and Quicken are very different applications. QuickBooks is designed for small to medium size businesses and Quicken is strictly a personal checkbook style accounting package.
If you are in the market for a personal accounting system you might also take a look at MoneyDance, a genuinely cross platform app written in Java and unlike Quicken its data files are directly transferable between Macs, PCs and Unix machines.
QuickBooks has been included with some Macs on the disks.
From a G5;
iLife (including iTunes, iPhoto, iMovie and iDVD), QuickBooks for Mac New User Edition, FAXstf, Art Directors Toolkit, Microsoft Office v.X Test Drive, FileMaker Pro Trial, OmniGraffle, OmniOutliner, GraphicConverter, QuickTime, iChat, Safari, Sherlock, Address Book, iCal, iSync, DVD Player, Mail, EarthLink, Acrobat Reader, Classic environment and Apple Developer Tools
Was able to install QuickBooks NUE 2005, version 7.0f2 from the Mac OSX Install disk. There was a shortcut to installing bundled software.
There's a menu option in the QuickBooks app. that allows me to import data from Quicken. What bobw has listed is pretty close to what I have as part of my bundled software.