If you have a boutique MIDI controller that doesn't come with a MIDI remote script for Ableton Live or if you want to add your own quick access controls instead of using the available control surface, this meant mapping parameters
This is the video version of the second most checked out written tutorial. It explains how to set up any MIDI controller with Ableton Live.
LiveControl 2 just came out. It's a Lemur template for the iPad and it's free for all owners of Lemur. It's very easy to set up and offers full integration with Ableton Live. If you're looking for video tutorials for LiveControl 2, they're this way.
Even though Ableton Live comes with a lot of MIDI remote scripts aka Control Surfaces, there will be times when you have to install one yourself. Some controllers require a special script to be installed and there are also a lot of helpful user scripts you might want to employ.
Before you can start having fun with your MIDI controller, it needs to be configured in Live - this goes for MIDI keyboards and all sorts of other controllers sending MIDI data. If you bought a MIDI controller that is supposed to be plug and play... well, you still need to set it up in Live. Plug and play only means that you don't need to install any drivers for it. If you don't have a MIDI controller, head over to the tutorial that explains a way to use the computer keyboard instead.