I am snapping a lot of pictures and lots of them I upload to Facebook. Is there any plugin out there to tag people in my catalogs?
At this moment I don't know any plugin that will do that. You can combine Picasa and Lightroom... more information on google http://lmgtfy.com/?q=lightroom+facebook+tag+people
Jeffrey Friedl produces a number of excellent Lightroom plugins and I notice he's got a new one for importing face data from Picasa:
I haven't tried it though, so I can't say if it does what you're after, but it might be worth a look?