Ableton Live has 3 different versions; Intro, Standard and Suite (We recommend Suite). They share common features, but Standard and Suite have additional features, instruments, effects, and Packs. Max For Live is only available in Live Suite.
See the comparison breakdown on their site.
Buy Ableton directly from their site here.
There are also resellers such as Sweetwater and Musicians Friend that may sell a bundled package that includes Ableton Live and a Push2.