http://isohunt.com/torrent_details/76595329/cs4+master+collection?tab=summary
if you already have cs4 and you just need to activate it, click the above link, download just the activation disabler.cmd and the keygen.exe. disconnect from the internet, run the setup, insert the generated key, and then run the activation disabler (as admin) before connecting back to the internet or running cs4