That's a pretty broad question, especially if you are coming into it blank. What you choose will depend a lot on what you are comfortable with, what you want to do in the way of backups. Which distribution you choose is one question, what you want to accomplish with backups is another question, and then what software and hardware to use are two more. And there are lots of options for all of those.
There is an O'Reilly book on the topic http://oreilly.com/catalog/9780596102463/index.html
, and Curtis Preston, the author, has a companion website http://www.backupcentral.com/
That book focuses on open source software, with some mention of commercial options.
You can also browse through some of the links here http://www.linuxquestions.org/bookmarks/tags/backup
If you want some particular suggestions, then probably every respondent will have some different suggestion. For your particular setup, maybe take a look at BackupPC. It's probably not worth it to get into the enterprise class products unless you really need them and are willing to go the extra mile to learn them and get them set up. But, you'll have to tell us a little more about what you want.