Workbench 3.0/3.1 disk in ADF format. - You can either transfer and
convert from the ones originally
supplied with your Amiga or buy from http://www.amigaforever.com/
If you legally own the full 6 disk set of Workbench 3.1 then
you could search google for them.
A 3.0/3.1 Kick-Start ROM Image. - You can either use the ROM
from your Amiga or buy it from http://www.amigaforever.com/