Hi Ambika,
I have also tried the same sometime before. Application manager contains several methods. You can find the details here. http://help.adobe.com/en_US/livecycle/9.0/programLC/javadoc/index.html. getApplication should return the specified application in an object format. Basing upon the input as applicationName, applicatiodId. You can save it as .lca. But I am not sure whether the lca would be valid one. If you try to import that .lca file through adminui and try to deploy it. It might not work.
Regrading saving that file in other locations through LAN is not possible. Because the FileUtilities option allows to save some file in the system where LiveCycle server is installed. In order to save the file to some other location you need to create a share folder and you need to grant access properly.
Thanks,
Bibhu.