more tutorials:

vampire makeover
light explosion text.
Ice text.
Glass text effect.
Bloody text.
Create realistic vampire fangs.
Create a Smoky Eye make up.
Changing Eye color and eye retouching.
change hair color.
Making dark and cold photo effect.
Creating ghost photo.
Drawing fake blood.
Create forum signature in photoshop.

Creating a Ghost photo in photoshop.

Step 2

Open a picture of a person who you want as a ghost, and make it greyscale (Image > Mode > Greyscale.
I chose this girl:

I made her look a bit more dead by deleting her irises:
Select the Dodge ToolDodge Tool
Choose a small soft brush (about the size of the iris, hardness set to 0%)
Set the exposure to 50%
And apply it several times on her irises, until they disappear.
dead eyes girl

Step 3

Use any selection methood you like to select your ghost, and paste it on the background image.
background with girl

Go To Edit > Free Transform
Click On the chain icon in the transform menu to lock the width/height ratio.
lock the width/height ratio.

Now you can move her and change her size.