The developer tools you need for 10.2.8 are the ones called "December 2002 Mac OS X Developer Tools". To find this download, go to
http://connect.apple.com, login, then click "Downloads" and "Developer Tools", and scroll to the bottom.
The Integrated Development Environment (IDE) that comes with those tools is called Project Builder. Xcode is the name of the new IDE that comes with the tools for Mac OS X 10.3 and later. But this doesn't matter -- you don't actually use the IDE to build wxWidgets or aMule, just the compiler: gcc.
If instead you want to upgrade to Panther, your best option may be to buy or borrow an external DVD drive. I don't know which version of the iBook you have, but hopefully it supports Firewire or USB 2. You might want to take your iBook and your Panther DVD into an Apple Store or other computer store and see if they will help you do the install. An authorized Apple reseller may even be able to exchange your DVD for CDs. (I assume it is a legitimate copy. If not, I don't want to hear about it.)
If your iBook has Firewire and you have access to another Mac with a DVD drive, another possibility is to boot the iBook into
Firewire Target Disk Mode, mount it as an external drive from the other Mac, and then use that Mac to install Panther onto the iBook's drive.