While not being an authority on either Sitecore or Rocks, i find the tool very useful for navigation and searching at the moment. One problem I did encounter was a lack of documentation. That said, Jakob Christensen addressed the query analyzer syntax documentation on a question I asked over here.
In short, use the HELP keyword, for instance type help select and you'll get some detailed help.
You can also use scripting commands from the sitecore explorer
select @title, @text from /sitecore/content//*[@@templatekey = 'sample item']
select * from //*[@@id='{0DE95AE4-41AB-4D01-9EB0-67441B7C2450}'];
you will need to use identifier escaping since field names can have spaces so enclose them with # on each end as in select @#Long Text# from /sitecore/content/Home