I've read up on Font book and I see how to make a new collection, say of favorite fonts. I'm not sure how to then set things so I am only seeing that font list when I'm working in photoshop, and not have to scroll down through ALL my fonts to find one font. Help much appreciated.
Sets don't control which fonts an app sees, it's all whether or not the fonts are activated. If you have all of your sets on, then all of the linked fonts will appear in all apps. To reduce the list, you need to deactivate fonts you currently don't need access to.