You do not have to install older versions to install an upgrade. You only need the serial number.
Thanks Bob, the problem is that when my software was taken, it was taken with the box etc, so the serial number went with.
In fact everything went, including my time machine. The only thing I was left with was the Mac itself because I had it with me at work when they broke into my house.
If you registered it your serial number will be available from your account at Adobe.com.
Thanks everyone. I didn't register my software (stupid I know).
Unbelievable I know, but I found an old file on my husbands computer with the serial number so I am saved.
thank you all again.