Can you buy a external microphone for the Panasonic HDC-SD60K camcorder?

I really want to have an external microphone because, in my opinion, it makes a big difference. but i have a very tight budget and I don't think i can afford one built in. Can I buy one and just put it somewhere on this camcorder? how much would that be? I haven't bought the camcorder, but i like this one. If there are any camcorders under 400 $ that already have an external microphone (not likely) that would be really nice too. Or just really good audio quality.