Ekim,
I had this same exact problem (No "get model" button and no saved file after it supposedly "saved".) So here's what you'll need to do...
Go to this website:
http://sketchup.google.com/3dwarehouse
Now you'll basically be looking at Google's 3D Warehouse site outside of Photoshop. Now all you have to do is navigate to the desired model, click the pull-down arrow on the "download model" button to reveal 3 options. The bottom option, to download a "collada" .zip file, is the one you want. Once downloaded, unzip and you'll get a folder with the name of your model. Inside it is another folder called models. Inside of it is a .dae file. This isn't the .kmz you were probably expecting but Photoshop seems to recognize it in a similar way and also lets you interact with it in the same way.
Hope this helps!
Eric Mousel
Creative Services Producer
ABC17/FOX38/MyZOU32/ABC StrmTrk 24/7
