I suggest that before downloading addons first check and see if there is a Download count for it, to tell you how many times people have downloaded it and if there is a star rating of any sort. Most addon sites have a place for people to place comments about it below as well.
Personally I only download addons form curse, wow interfact, ace etc. All the well know, top google reslt searchs.
I suggest if your looking for an addon, don't go to google and search the addon name, rather search for "world of warcraft up-to-date addons", then go to one of the top sites listed there and then search for the addon via that site.
But yeah, contact Blizzard, ingame and out then the waiting game starts. I'm afraid sometimes blizz can take a few months to restore you items.