Since there are lots of ALP Packages that could be installed on older Ableton versions, i compiled a list of Packages in the Web that will work as well with Ableton Live 8 (although sometimes it is stated they would only work with older versions) - sometimes a bit tweaking is required, but nothing more than moving some files around in the file browser of Ableton. Besides the obvious ressource, ableton.com, i compiled a list of free 3rd party package ressources, that will keep your sequencer experience interesting. For importing and recovering old Ableton Sets i wrote a specific article, though some of the compatibility Packages are also listed here. The steps described and the package recommendations are for Mac OSX as well as for Microsoft Windows. If you know of some more ressources not listed here, please drop a comment!