Hail my friends! Joe, here's where the channels would be, in thier own tab behind the Layer tab. Alphas are, in my experience, often overlooked but extremely powerful if used correctly. You can add an alpha channel to the channel list just like you add layers to a layer list. The alpha channel will show up as black. You then can paint, paste, or filter your desired effect into the file. Alpha channels are black and white and shades of grey, with black being untouched and white being the most effected by whatever change you're making.