You can purchase Valvoline MaxLife Automatic Transmission Fluid at Walmart. Fluid is synthetic, it works great and compatible with Toyota WS fluid.
For me, I have a Pela oil extractor. I use it when changing engine oil, transmission fluid, steering fluid, brake fluid or coolant. Just run the engine few minutes to get the oil or fluid warned up, and stick the flexible metal hose down until it bottoms down the dipstick. Just few pump, it sucks out all the old oil or transmission fluid out. It works great, no mess and I don't have to remove the drain plugs again. I changed the trans fluid in my 2009 Vibe two days ago. I poured entire gallon fluid into the trans and it was a little too much. I used the pump to suck out 1/3 of a quart. I have 6 cars to maintain, so my Pela oil extractor is a great investment.