My favorite resource for determining gypsum assemblies for fire protection is the GA Manual. The 2009 manual is now available online. It sorts fire assemblies by the location of the assembly and then by the number of hours each one provides. It also provides STC ratings.
The Gypsum Association has returned to the single PDF format that they used in 2003, I much prefer this over the chopped up 2006 manual. With this edition of the manual they’ve added 89 more assemblies and deleted 31. As always its important to read the notes at the beginning, they give you a lot of additional options.