I'll answer both in one response.
TuneCore is happy to take albums that haven't been physically produced. Just burn the album to a blank CD and send it on to us. It's all in our FAQ. Read more here:
http://www.tunecore.com/index/faq#WhyCD
We hate to see someone cancel, but it's easy to do it. Just send an email to our cancellation department and it's done. You can do it any time. If you do it for an album that's been with us less than six months, we charge a $20.00 fee, mostly as a discouragement. We don't want people putting things up and taking them down willy-nilly. After six months, no fee, we'll just take it down. To close the whole account, we'll take all your albums down, transfer any money that might be in your account to you and delete your account. BUT REMEMBER, we're non-exclusive. You can get picked up by a label and still be a TuneCore client, no problem. If you really have to cancel, should only take a few days.
Right now, you're correct, there's no place to put your label name. The problem is actually on the iTunes end. We could have you put in a label name no problem, but iTunes doesn't collect that information. Weird, huh? Right now on iTunes you can't search for music by label. At the moment, most labels are "sneaking" around this problem by putting their name in the copyright field. With TuneCore, that field defaults to the band/artist name. The moment iTunes and other stores/services come up with a reasonable way to include label names, we'll be there to pass that information along.
Thanks!
--Peter