Exercises to get rid of back fat?

I'm trying to tone everything on my body. For the past month or so, I've been doing at least one chest/back workout a week. I'm wondering if I need to do more than that to tone the back fat and get it to go away, or is one a week going to be sufficient along with losing weight? It's getting very disheartening to see my body toning up but the back still stays the same. Anyone have any ideas? I'd be more than willing to share my back exercises if that will help.