Note: I want this because i got the 40GB PS3, and I already almost used it all up. I collect TONS of games, downloads, music, and pics. Thats why i want the 300GB Hard-Drive.

Ok so I want to get like a 300 or more GB hard drive for my PS3. However, if I were to get one, wouldnt it get rid of all of my saved stuff if I switched out the hard drive? How do i prevent this? (Like, how do I save all my data?)

If there is a way, what is it and how much does it cost?

Also, where can I buy PS3 Hard-Drives? Do i just buy a regular 300GB Computer Hard-Drive?

you need a hard drive for a laptop , it has to be a sata 2 1/2 inch 5400 rpm drive , normally you'll find them in 160 , 250 , 320 and 500 gigabyte sizes . you probably don't need bigger than 250 gigabytes .
with 2200 songs , 60 games , 35 movies and every season of 24 I use 145 gigabytes only .
to do a backup you need an external hard drive in fat32 format then go to system settings to do a backup .