Hi Lisa,
I don't have a sample to show you but wanted to say that whenever I want to quote a 'package' for a client (which is something I have just recently switched to in many cases, as opposed to hourly) I've just been taking it on a case-by-case basis.
I've seen examples of these kinds of packages for services like
SEO or website maintenance but not for social media, though I'm sure they're out there.
It seems like a great marketing move, to create these packages and it makes it easier for people to hone in on 1) their ideal price point and 2) their particular level of need.