I've used aluminum backpacking stove fuel bottles made by MSR to carry extra gas on my motorcycles. I've also carried cheap, quart sized alumimum canteens.
If you are looking to put gasoline in plastic containers, look at containers marked HDPE (high density polyethelene) which is what plastic gas cans are made of. Most shampoo bottles are made of HDPE. My wife buys quart sized shampoo and conditioner. I've used empty ones for my gas trimmer. Of course they are cheap (free!). The only problem with shampoo bottles is they use a hard plastic cap that can break if the bottle is dropped and lands on it's cap.
Polycarbonate (Lexan) Nalgene type water bottles are gasoline resistant as well, just make sure you mark it as gas so people won't try to drink from it. Also, once you put gasoline in it, you can never use it for water/beverages again. The nice thing about them is that the are cheap and virtually unbreakable.
