Can I access my Ubuntu One account via FTP? if so, how? I want to use my backup script to send to my account on ubuntu one.
Yes you can. See James Henstridge's u1ftp, at https://launchpad.net/u1ftp, and some description of it and videos at http://www.kryogenix.org/days/2012/09/11/accessing-ubuntu-one-file-storage-via-ftp-from-any-os.
Not right now. If you are after a way to upload files to Ubuntu One that are not synchronised to your desktop/laptop and you have some programming experience, you might want to look at our REST files API:
If you create a new volume it won't automatically be synchronised to your computer, so if you upload files to that volume they won't be copied back to your computer by the synchronisation daemon. Information on how to authenticate against this API can be found here:
The auth documentation is still being expanded, but there should be enough in there to get you started.