How to download ps3 update

If your PS3 is connected to the internet, you can download and install it directly to the PS3 like this:

http://us.playstation.com/support/systemupdates/ps3/ps3_update_system/index.htm

Or you can use the PC version like this:

http://us.playstation.com/support/systemupdates/ps3/pc_update/index.htm

Anyhow, if you downloaded it with firefox, just go to the directory where you saved it and drag it over to your USB drive.

You can hit CTRL-J to bring up your downloads window, right-click on the PS3 update file and select "open containing folder".
 
Follow the links and instructions left by Hawkeye22. By default your Download directory is C:\Users\<Your ID>\Downloads (for Windows Vista/7) or C:\Documents and Settings\<Your ID>\Downloads (for XP and prior).

And remember, as stated in the "PC Version" link, the folder structure on your USB drive has to match the instructions exactly... PS3 ---------> UPDATE ---------> downloaded update file...

If you can use the wired or wireless functionality of the PS3, that will be the most convenient. I've had to go the manual update route once or twice and it is easily doable, although a much bigger hassle in comparison. Good luck!