The orange wedge on the beer is not a Belgian thing at all, probably a local novelty. Belgium has over 400 types of beers, some flavored with fruit, some with up to 12% alcohol.
I've seen some advertisement in GQ from Stella Artois, Hoegaarden and Leffe.
Looks like they are being sold in USA now, I personally like Jupiler.
If you are into Belgian food, try your Flaamse fritte (French fries) next time with mayo. Here is a link with a list of Belgian beers: Liste des bières belges