If you use the version of ATK2011, the xyz file of a configuration can be exported using the options "File--->Export Configurations....---->Files of type" in the "Builder" tool, as mentioned by Anders Blom.
Since you used the version of ATK2008, the xyz file can not be exported in the above manner. It can be done in a complicated manner:
1). transfer the configuration into to the "Script Editor". In the window of "Script Editor" for you configuration, add the following line at the end of the nanolanguage script:
nlPrint(the name of your configuration)
2). drag the script file in the 1st step onto the "Job Manager";
3). the atomic coordinates will be printed out in the log file. Copy them into an ascii file, edit it according to the XYZ file format and then save it as a xyz file.