How can I edit a locked background Layer?

Simply double click the 'Background Layer' in the Layers Palette.

Then at the 'New Layer' prompt dialog give the previous 'Background Layer' a new name. Otherwise Photoshop will default with the 'Layer 0' name.

Alternatively, select the 'Background Layer' in the Layers Palette.
Then go to the 'Layer/Layer From Background' menu command option.
Then continue as in the layer naming option mentioned above.

Tip: Alt + Double Click (Mac:Option +Double Click) to unlock & bypass the naming process in one shot.

How can I find out if Photoshop CS is worth the upgrade?

Photoshop CS is robust for Digital Photographers, Graphic Designers & Web Professionals. Depending on your area of expertise the best thing to do is to download the tryout version and take it for a test drive.

Download tryout version here.

Where do I get additional help on using Photoshop? Immediately start with the 'Help' system that comes shipped with Photoshop.

To access the Help files:
A. 'Help/Photoshop Help' menu command option
B. Hit the 'F1' keyboard shortcut.

Where is the 3D Transform filter in Photoshop CS? With Photoshop CS the 3D Transform filter is no longer installed by default. Instead you have to install it manually via your original installation cd.

How do I disable the Photoshop CS Welcome Screen? Simply open Photoshop CS and at the Welcome Screen prompt untick the 'Show this dialog at startup' option on the lower left of the screen.