I've got a constant soundtrack in my head. There's always a song running through my mind. I spent a bit of time worrying about whether or not this is normal, but I've decided it's not something I'm going to be worried about.
The soundtrack changes constantly, and is very easily influenced by outside forces. If someone mentions India, for example, I may get Finland by Monty Python in my head, but I'll have replaced "Finland" with "India", and then it will merge into the real version of the song. I can usually follow the train of thought that takes me to a particular song. It's a nice little look into how my head works.
Generally, I know the words to the song in my head. If I don't know the title or the artist or every single word, it's usually pretty easy to find. The internet is such a helpful place. Even a snippet of a chorus or verse is usually enough to find out the name of a song.
And then there are the songs I don't know. Like the one I've got in my head this morning. The ones that I only have a bit of a chorus, with made up words. It's hard to look for "Can you feeeeeeeeeel" or "Do you feel the [something], can you hear the [something]" when you're not even sure if those are the real words. I'm pretty sure they're not. And even if they are, do you have any idea how many songs contain the words "do you feel"? At least 26413, according to this website. (And no, it's not Ain't That A Bitch by Aerosmith.)
My best tactic for getting rid of a song I don't know (or don't like - that happens more than you'd think) is to get another one in my head. Getting someone else to sing a song, or reading a song title, or hearing one on the radio is usually the ticket to annoying-song-be-gone.
Except it's not working today. And I still don't know what that damn song is.
Do you feel the something, can you hear the something? Can you feeeeeeeeeeeeeeeeeel?