moved

PowerPC port of Ubuntu is here

Direct link to CD image
http://cdimage.ubuntu.com/ports/rele...op-powerpc.iso

Burn ISO image to a blank CD

I note you've asked about installing without a CD
It's easiest by far if you can just install from the CD
(just borrow someone's USB cd drive if you have to)

However,
info on installation without using a CD
https://help.ubuntu.com/community/In...thout%20a%20CD
(I've never actually installed a linux distro without using a burnt CD, so I don't think I'll be a lot of help)