If you have BESA, the folder c:\besa\montages\channels
contain a variety of channel location files that can
be imported in EEGLAB.

See also EGI ftpsite ftp://ftp.egi.com/pub/software/besa/

Both 3-D spherical ".elp" files and 3-D carthesian ".sfp" files 
can be imported in EEGLAB.