If you can't gain weight naturally, steroids don't help. Think of food as your bricks/mortar, and steroids as your workers. It doesn't matter how fast your workers can work (steroids), if you don't have sufficient materials (food) you can't build a house. Plain and simple.

Steroids aren't magic, and muscle doesn't come out of thin air. You need to eat to gain weight wether or not you use steroids.

You don't need an appetite to eat. Just eat. How many grams of protein/fats/carbs do you eat every day?

BTW, I went from 135 to 185 (keeping the same bodyfat) in 1 1/2 years natural, all that was involved was food + heavy lifting. So I know what its like to be small and what it takes to get big.