Shipping bags

Anyone know a good place to pick up some plastic bags for shipping fish? I'm pretty sure ziplocs won't cover it lol

Or another question would be, does anyone know any LFS that could ship for me (paying of course!) in the South King Co. Area?

Try A Place for Pets. When I needed to ship some fish a few years ago, I went in there and was able to purchase bags and bag buddies. They even gave me a box that fish had been shipped to them in and offered to bag them up with oxygen for me.