It's on the drivers side of the engine compartment directly under the air intake chamber assembly. I think the best access is by removing the DS front tire and the little wheel well skirts. Don't know if you're going with an aftermarket product, but you're generally best advised to stick with Toyota parts. Apparently the install is a little tricky because of the tight quarters. One tip I've seen that's supposed to make the install easier is to notch out an opening on one of the bracket ears on the fuel filter. That way you can go ahead and get that mounting bolt started, then bolt the other side and rotate the filter to slide onto the first bolt you got started. Hard to explain, but hopefully that makes since.
I am going to go look but my air intake and filter is on the passenger side.