Once you find a good method for framing, you should take a look at creating a droplet to make it easier to add frames to your images at a later date, in bulk. The first suggestion is the easiest but of course it eats into your image. The second is probably the better solution as it doesn't snipe any parts of the image off.
But definitely investigate droplets. Basically you record all the actions you take to create a frame for an image and using those actions you create a little mini-application that you can drag your images onto and it'll frame them for you using the actions you recorded. It's a nice way to save time.