For safari users, resurrecting your Favorites Menu is reasonably easy.
Go to your Finder tab and, holding down the Option key, select "Go"
and then "Library"
You must remember to keep holding down the Option key or the Library menu will not popup.
Now, open the Safari folder and you'll see a file labelled Bookmarks.plist. This is file safari has set aside for storing all of your bookmarks.
Now, launch Time Machine by clicking on its icon in the dock
The Time Machine interface will also display the Safari window. Now, it's just a matter of going back in time until you locate the Bookmarks.plist file saved on your hard drive before you inadvertently launched the whole thing into oblivion.
Click Restore and the system will ask you if you'd like to keep the original file, replace it, or keep a copy of both. If you liked your bookmarks the way they were and would like them back,
click "Replace the current file."
Should you decide to keep both, the original file will be named Bookmarks.plist. If you choose this option, Safari will display a list of bookmarks that has been culled together to make you a new bookmarks list. Something you may not be happy with at all.
To make the older, more complete file your default bookmarks list, change the name of the partial list to something else, like BookmarksII.plist, and keep the older file as your bookmarks.plist file. This will alert Safari that you would like to use the older file as your default bookmarks list.