Light Textures

Suddenly light textures seem to be all the rage in icon making. I use Adobe Photoshop 7.0 and I have absolutely no idea how these textures are supposed to be used. Can someone please help me?

Is there a special way that I have to install these textures into Adobe Photoshop 7.0?

Does someone have a link to a tutorial that can help me out some?

To give you an example of what I'm talking about:

When I download these light textures, for instance, from teh_indy, they are all big images, just regular pictures of light. None are in brush format and there are no directions or hints as to how they are to be used. They make gorgeous icons, so I'd like to know how to use them if possible. Perhaps they are just meant for Paintshop Pro and that's why I can't seem to figure this out? I'm relatively new at icon making...and every bit I learn helps me get better.

My apologies if this has been posted before. I know how annoying it is to see the same question posted several times :x I'll be glad to delete my post if someone would kindly point me to where the answer to this is archived.

Thank you in advance for any help!