How to search terminal output
Finding text in scrollback is a weakness of most terminal emulators; the only ones I know of that provide it are OS X Terminal and Terminator. That said, you could run GNU screen in any terminal and search its scrollback buffer in copy mode.
If you are running a gnome-terminal (default GUI terminal on ubuntu) you can hit shift+ctrl+f, type your search terms, and hit enter. Still graphical, but no mouse required.