Here is a blog my team is working on at Accenture which is intended to be a complete beginner's guide to Cassandra. I'm still updating a few posts based on DataStax's recommendations and I need to add the last three posts (will get this done soon), but you can start checking it out via this link:
https://sites.google.com/a/techlabs.accenture.com/cassandra - Sameer
