You can set up nightly backups using the SQL Maintenance plan, then backup that flat file with whatever backup software you use for your other servers. There is backup software available that will back up live databases as well, but that would take research and planning to find the one you would like to use for this purpose. We use Tivoli Storage Manager’s Data Protection for SQL, but we have the entire TSM system up and running with TSM server and robotic libraries, and disk space to back up to. It is a rather large backup operation for many servers which we perform.
Yes, live backups can be taken using the BACKUP DATABASE command. This will backup the database to a binary file which you can then move to tape. To backup the transaction log use the BACKUP LOG command. You can schedule this to happen using any job scheduler including the SQL Server Agent which is installed by default when you install Microsoft SQL Server.
If you choose to use the maintenance plan all it does is use the BACKUP DATABASE and BACKUP LOG commands to backup the database and it uses the SQL Agent to do the scheduling.