Importing Brushes from Image Packs

For the life of me, I cannot figure out how to import brushes from image packs. I got the whole "unzip" thing down, but I can't get them into PSP7. I have googled tutorials until my eyes bled *little sarcasm... my eyes didn't really bleed -_-* and they have told me nothing. Well... I got go to "files," "import," and then "custom brush" but it there is no option for "custom brush" when I try to do that. So.. I don't know. If someone could help me, that would be wonderful.