How to merge textures into single image Hi, beginner here. 

I have some mesh with 4 different UV maps. Each map has assigned a texture. Is there any way to join this textures into single image without changing their position?
Im working in Blender render.
Look up Blender Texture Atlas.

also,
You can create a new image, in the image editor, large enough to hold the resolution you want. 
Then, create a new texture layer, to use the new image, and bake the original textures to the new Texture. You will just have to move the UV maps around so they don't overlap during baking.

Info on that here and here.