I would like to purchase an older version of Photoshop such as CS3 or CS5. I know from experience at work that the older versions are quite suitable for my needs. I'm hoping they are available for prices lower than when they were first released. I'd be using it at home on a fairly new OS X Mac. Did not find info on this on the Adobe website. Am seeing prices ranging from $350 to $2,000 on other sites. Don't know what to believe. Anyone know of a trustworthy site I can go to buy CS3 or CS5? Are license transfers o.k.? Maybe I can find someone who has CS3/5 who is no longer using it or any of the upgrades? Could these older versions even run on OS X? Thanks.