I think a good start for beginner will be the Big Data course from Coursera
For example I've learnt the basics of MapReduce techonlology.
How about Hadoop: The Definitive Guide, from O'Reilly Media. It covers everything to do with Hadoop, MapReduce, HDFS and more.
Besides the Cloudera resources I'd highly recommend you the reference books from O'Reilly :
Cloudera
You might also check it's data science kit as well.