I have found the website:
http://usmilitary.about.com/od/enlistedjob1/a/navyjobs.htm to be very helpful with information about any Navy job. Sometimes the things posted on the website are out dated, but it is better than nothing. For your position it said:
"The Logistic Support (LS) rating is a new rating being established, effective October 1, 2009 by merging the Storekeeper (SK) and the Postal Clerk (PC) ratings. For details, see Navy Administrative Message 326/08.
Losgistic Support Sailors manage inventories of repair parts/general supplies and distribute mail for ships, squadrons, and shore-based activities. They procure, receive, store and issue material and repair components. They utilize financial accounting and database systems to perform inventory and financial management functions. Additionally, they sort and distribute all official and personal mail, manage money order and stamp inventories, and maintain financial and inventory reports.
Typical duties include:
•ordering, stocking, and issuing repair parts, clothing and general supplies;
•maintaining financial records and accounting systems; maintaining inventory databases for material stocked in shore based warehouses and ship storerooms;.
•perform duties associated with hazardous material control and management;
•Organizing and maintaining databases, correspondence files, and reports;
•Maintaining logistics and financial publications and CD-ROM libraries;
•managing and operating Navy post offices, ashore or afloat; s
•orting and distributing all classes of mail and parcel post;
•processing and dispatching mail;
•directing the routing and transportation of mail;
•performing counter operations similar to those performed in United States Postal Service offices, such as selling stamps, handling money orders, preparing claims, tracers and inquiries; preparing and maintaining postal records and reports;
•requisitioning, controlling, and maintaining postal supplies and equipment; maintaining security for registered, certified and other special classes of mail.
Working Environment
LS Sailors work in offices, shore-based warehouses, air cargo terminals at naval air stations and in storerooms aboard ships. While they work closely with other people, their tasks usually require independent decisions. The diverse working locations associated with this rating provide an excellent opportunity for learning a wide range of inventory database management, financial management, procurement, and warehouse management skills. SKs work aboard all types of ships and shore bases throughout the Navy."
Hope this helps!