Source to usemono.net, a Mono advocacy site aimed at .NET developers.
Pull requests welcome for copy or resources. Project should work out of the box on Windows, OS X, or Linux (provided you have .NET or Mono installed, of course).
Ubuntu:
Use this ppa. Install mono-complete.
Alternatively, use this ppa and install monodevelop 5. It will all be installed to /opt
to remain self-contained, but everything should work fine.
CentOS/Fedora:
Use this OBS repo and install monodevelop-opt. Like above, it will be contained to /opt
but should all work correctly.
You can also use the Vagrant box found here which will install Mono via puppet on startup. I'm in the process of making that better and will open source the module.