Mixxx - The most powerful free DJ software in the world.
Guitarix - Guitarix is a simple Linux Rock Guitar Amplifier for https://alternativeto.
Zulu DJ Software - Zulu DJ Software is the best tool for singers and musicians.
ToneLib GFX - The perfect custom tone with a complete guitar studio in your computer
VJ6 - If blending music is your essential thought process, you might need to search somewhere else for your DJ blending software.
Rakarrack - Rakarrack is a richly featured multi-effects processor emulating a guitar effects pedalboard.