Fungus on tomato?

Today I noticed some little brown spots on my supersweet 100 tomato leaf. I think it might be some sort of fungus since it looked a little fuzzy...I need to research organic or homemade ways to fight fungal infection. I've strayed away from the "organic" strategy from the standpoint of fertilizer (I'll explain in another post), but I want to stick with using organic methods for fighting insects/fungus/bacteria.

If you have any suggestions, it would be much appreciated!