Photoshop Trials

I've a digital photography module this term - YAY - and it's going to involve some fairly intensive training in Photoshop CS2. I know my way around photo editing programs generally, but I'm sure there are plenty of gaps and I'm looking forward to having a professional around to show me what I'm doing wrong. The university has suites of Macs and high-end printers, but as they're two hours away I think it's sensible to get hold of Photoshop at home.

The student version of CS3 is £140, and while waiting to afford that I figured I'd download the 30-day trial. I picked up an enormous tutorial book from the library so I could have a play around, and promptly discovered that I already installed the trial last year. My 30 days are up, so I can't get in.

I know I can get around this by reinstalling Windows; there must therefore be something somewhere I can delete to reset the 30 days. Obviously Adobe make this difficult so people can't use the program indefinitely, which is fair enough. I could use a keygen and (illegally) unlock the trial to the full version but I have too much respect for my computer to start messing around with warez stuff. And I don't want to feel like I'm ripping anybody off. 30 days is more than reasonable...I just need them again

Not a big worry, in the grand scheme of things. Little frustrating, though. I'll try to install it on my parents' laptop instead. I can only steal that a couple of times a week, but it's more powerful than my home computer anyway...