Sony, via the US PS Blog, has confirmed that the demo for their upcoming PSP action title, God of War: Ghost of Sparta, will be out tomorrow. God of War: Ghost of Sparta is the second game developed by Ready at Dawn in the series in this much successful series, and is set between God of War and God of War II. It will see the exploits of Kratos as the Ghost of Sparta.
Keep looking out, we might have a preview up soon.