UV Paint, T4exture and mapping

With a complex mesh landscape, I need to uv map sections of a mesh to apply colour and texture to small individual sections.
Sections are mountainous, plains (sand, gravel and grass short and tall), forest, cliffs and sandy beaches, water’s edge of lakes.
Each section must be different but blend in to adjoining sections
Sometimes on overlapping unwraps.
I understand painting and texturing on the mesh or on the UV map.
I create new data blocks for each section.

Highlighting mesh sections unwraps well but deselecting and then selection another part of a mesh displays the first and subsequent unwraps all at once. Very confusing.
How does one delete, hide or deselect each previous UV unwrap map in order to select the next highlighted section of uv unwrap?
and
I have found that opening a white background image 1024 x 1024 makes the unwrap appear within the dimensions of that white background, I use the pencil to make that map black lines for a screen shot to use in Gimp.
Occasionally the unwrap is so large it dwarfs the white background and it cannot be selected, deselected or shrunk. Don’t know what to do about this.
Are there tutorials on how to dispose of, erase, deselect finished unwraps please?
I have Fedora 8 with Blender 2.47 Intel mb, 2 g mem nvidia 8600gt video card
TIA
Roger

You can use stencils. They’re black and white images painted over something, the colors separate textures from each other. Google.

STENCILS! Thank you B3D00!
I have sort of same problem as hovergo. Here i’ll go for a Google-Blender tour!.. -->

Thanks can you tell me more please, I don’t know about stencils

Maybe you’ll find few hints here:

http://feeblemind.tuxfamily.org/dotclear/index.php/2005/02/27/16-didacticiel-usage-des-masques-de-textures-tutorial-using-texture-stencils

and here:

http://en.wikibooks.org/wiki/Blender_3D:_Noob_to_Pro/Landscape_Modeling_II:_Texture_Stenciling

or here:

http://wiki.blender.org/index.php/Manual/Map_To

Good luck! :wink: