I have CS2, since it is no longer supported by Adobe can I update to the newest version of Creative Suite or do I have to purchase it outright

If you do look at buying CS6, you need to be aware that it is 3+ years old and has NOT been upgraded to run on the latest Mac or Windows operating systems... so if you have a Mac newer than 10.7 or Windows newer than 7 the programs may not run

There is no upgrade path from CS2 to the most recent CS release which is CS6.  You would have to pay the full price for the suite, if it is available for sale where you are.

Check with the below link once :

Creative Cloud now includes Creative Suite Master Collection and Design Premium features