Hey, I recently found a Firefox addon that most of you have probably been using already (I'm a bit behind):
AdBlock Plus
It's on the list at https://addons.mozilla.org/en-US/firefox/recommended and works really well. For instance, I no longer see the graphic ads on Facebook or these forums!
Oh, and in regards to which provider to use, I just clicked the first one - I assume I won't be needing the foreign ones for now.