Although the main goal of this book is to create things from scratch, don't overlook stock photography services as a source for edges, shapes, or frames. Here, we'll use an image I found on iStockphoto.com (some other examples appear at the end).
Open the stock photo you're going to use, and select the area(s) where you want your photo to appear (in this case, I used the Magic Wand tool and the Lasso tool to make my selection).
Switch to your photo and press Command-A (PC: Control-A) to select the entire photo, then Command-C (PC: Control-C) to Copy it. Switch back to the stock photo and choose Edit>Paste Intoa layer mask is automatically created this way. If necessary, use Free Transform (Command-T [PC: Control-T]) to scale the pasted photo to fit (by default the layer and layer mask are not linked, so you can scale the photo without affecting the layer mask).
For some images, the last step might be using Free Transform. In this case, due to the nature of the stock photo, a couple more steps were required. I changed the blend mode of the photo layer to Multiply using the pop-up menu at the top of the Layers palette, then duplicated the layer by pressing Command-J (PC: Control-J). Finally, the blend mode of the duplicated layer was changed to Luminosity. This helped create the look of a somewhat faded, sepia photo.
Here the photo layer's blend mode was changed to Multiply
Here the duplicate layer's blend mode was changed to Luminosity
Here's another image from iStockphoto.com of an old photo border. In this case, it was a simple matter to select the black area of the stock photo and use Paste Into to add my image.
This photo edge was one of many I found on fotolia.com. I used the same method of copying my photo and pasting into the stock photo selection to create the layer mask.
Here's an iStockphoto image of an old battered Polaroid. Again, a simple Copy, Paste Into, and Free Transform and I was done.