If you need help with GSON, here are some people and places that will prove invaluable:
Home page: http://code.google.com/p/google-gson/
Manual and documentation: http://google-gson.googlecode.com/svn/trunk/gson/docs/javadocs/index.html
Source code: http://code.google.com/p/google-gson/source/checkout
Design document: https://sites.google.com/site/gson/gson-design-document
User guide from Google: https://sites.google.com/site/gson/gson-user-guide
Mkyong's blog: http://www.mkyong.com/java/how-do-convert-java-object-to-from-json-format-gson-api/
Official forums: https://groups.google.com/forum/?fromgroups#!forum/google-gson
Unofficial forums: http://stackoverflow.com/questions/tagged/gson
Java code geek blog post: http://examples.javacodegeeks.com/core-java/gson/convert-java-object-to-from-json-using-gson-example/
GSON applications...