for isometric-parts-1 look here

this set contains a lot of models from oga and the background used in the preview(background-image cc0)

first i list the cc0-submissions

http://opengameart.org/content/knight-statue, by yd

http://opengameart.org/content/knight-lying, by yd

http://opengameart.org/content/trashbox, by groemk

and here the non-cc0-submissions:

http://opengameart.org/content/barricade, by Sullivan, CC-BY-SA 3.0

http://opengameart.org/content/mecha-training-dummy, by Danimal, CC-BY-SA 3.0

http://opengameart.org/content/spyke-trap-low-poly-updated, by Danimal, CC-BY 3.0

http://opengameart.org/content/stone-jar

and

http://opengameart.org/content/netted-jar, both by Clint Bellanger, CC-BY 3.0

http://opengameart.org/content/mortis-and-tenon-table

and

http://opengameart.org/content/wooden-box-open, both by ulf, CC-BY-SA 3.0