How to edit application menus

I'm new to this list. :) I have had XFCE installed for some time on my Fedora 16 x86_64 laptop, but used it only as an emergency desktop in case I messed up Gnome. But after upgrading from Fedora 14 to Fedora 16 I have become a Gnome 3 refugee, and I am coming to like XFCE a lot. My XFCE application menu is pretty messed up. I have extra folders and application entries are scattered in the wrong folders. One new folder is "Other," and it appears that XFCE stuck everything it didn't know what to do with into it. Every time I go to launch a seldom-used application it takes a long time to wade through the folders trying to find it. After hours of googling none of the suggestions that I have found for editing the application menus work. For example, apparently there are desktop entries in /usr/share and in ~/.local/share/applications, but I can't find desktop files for some of the items that appear in the menu. I also can't find any place where the folders are listed. Alacarte ran briefly after the upgrade from 14 to 16, but after nearly a thousand software updates it won't launch at all. And when it did launch it showed only the menu that I was using in Gnome. I'd be happy to have the Gnome menu if there was a way to migrate it to XFCE. (I haven't ever actually logged in to Gnome since the upgrade to Fedora 16.) I really need to edit the application menus. I hope someone here can tell me the secret. I don't mind doing it manually; I just need clear instructions.