If I remember correctly it is on the third plateau on the right side of the trail heading towards the building. When on the right side get into the cooled lava rock and search in that area. The eagle wasn't whole when I found it, but is instead barely showing a gold side of itself like it had sunk into the lava and is trapped there.
The Knossos eagle is a little hard to find because it's partially buried. However, you can just run over it and still get credit. My guide has a map location and also a picture of what it looks like while it's buried.