Teradata learning resources
I would spend sometime over at the Teradata Developer Exchange, Teradata Questions (currently disabled), and the Teradata Forum. There is a wealth of information to be gleaned from these sites.

There is an Express version of Teradata that can be downloaded from here. This will allow you the opportunity to experiment with Teradata on your own computer. The VMware edition will probably provide you the most flexibility from a DBA perspective. The Windows version is great for developers who want to improve their understanding of SQL with Teradata.

Of course there are also questions about Teradata on Stack Overflow using the teradata tag.