Changing Text in a .PSD File

I have a .PSD file that someone made for me before I had Photoshop that I want to edit. I'd like to change the actual text of the image, but can't figure out how to do it. I can change everything about the text layers, except the text It's probably something very easy, but I'm a complete Photoshop newbie. Could it be that I don't have that font installed, or something like that?

The image is attached in .jpg format because the .PSD was too big. Any help would be greatly appreciated!

How can you change text layers with a JPEG?

Have you tried using the I text thingy and highlighting the text?

Yes, hit "T" to bring up the text tool... click-drag the text line you want to edit... it should highlight. If it doesn't highlight and creates a marquee, just try again until the text is highlighted.

Once it's highlighted then you can easily edit the text. Look for the text tool button on the top right-hand corner. It's actually called the Character/Paragraph toggle palette or something like that.

note: make sure you're on the text layer first, and that there is a big "T" for the layer icon.