Hi! We have some guidelines for wallpapers at: https://wiki.ubuntu.com/Artwork/Documentation/Backgrounds/
You can also find templates for Inkscape and GIMP there, for working at a recommended 2560 x 1600 pixel size and keeping the most common aspect ratios in mind. -- Thorsten Wilms thorwil's design for free software: http://thorwil.wordpress.com/ -- ubuntu-art mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-art
