What version of Acrobat?

What version of Acrobat do you guys/gals use for compiling multiple sheets into one file. I know that I definitely don’t need 7.0 professional. I had that 30 day trial from Adobe. Where can I obtain a cheap copy? Possibly even an older version.

Thanks

Forget it, I just bought version 6.0 Professional.

If you did happen to view this thanks!