PS3 Downloading

I have a question about downloading PSP games from the PS3. Do I just need to purchase the title and download onto the PSP with a USB cable, or am i reqired to get other hardware? If someone could answer this for me it would be great as i want to downdoad Kingdom of Paradise for $15 instead of paying $30 in my market.

If you're talking about downloading from the PSN, then just download it from your computer.

Go here: http://store.playstation.com
Sign up
Download the Network Downloader
Buy the game you want
Put it on PSP via USB connection
Play