Automatically Locate Included Images

You can do this the following ways:

1. Use the \graphicspath macro:

   \graphicspath{{path/to/image/}{other/path/}}
   

2. Define the environment variable TEXINPUTS to contain the path:

   TEXINPUTS=".:path/to/image:other/path:"
   

   Note the leading '.' (current dir) and the trailing empty field (default texmf tree).

3. Put your graphics in an own local texmf tree, so that they are found automatically. Then the path doesn't has to be defined. However this causes problems if you have multiple files with the same name in different directories.

The TeX Directory Structure (TDS) reserves the images "package" name for includable graphics. So if you want your graphics to be findable and to be TDS-compliant, put them in ${TEXMFHOME}/tex/generic/images.

(personal story, name drop alert) I brought this up on texhax ages ago and Karl Berry said he had completely forgotten about that convention despite the fact that he's TDS editor. Apparently it's not used by many distributions. But I've found it handy.