No Linkin Park PSD's are really availible on the net at this time. The PSD's Mike uses for his art(pending he uses Adobe) are not availible to the public as Mike wouldn't release his artwork in that form to the public as he no doubt spends countless hours perfecting them. However, there are grungy brushes in the internet that you may find to be Linkin Park-ish although they are not by Mike himself. You can find BRUSHES through sites such as "VBrush". (Which I think you may be able to find through google) and on that site they have a link to a site called .ABR which has some very grungy/rock related brushes. Hope I helped you towards the right direction.