I need to find this for cheap...

Not sure if this belongs here, please forgive me. I will remove it if it doesn't.

I've been using a copy of Adobe Photoshop to make graphics for my webpage. However I recently had to do a computer wipe and I no longer have the program. I need to know where I might find the latest version (7.0? CS? It's all so confusing) for as cheap as possible - retail is ludicrously overpriced! I don't care if it doesn't have it's box or I can't register it, I just want the program.

Thank you for any assistance!