If you plan to make Splunk part of your career path and goals, you'll want to expand your Splunk knowledge and experience by reading books (such as this one!), the Splunk docs, and getting some hands-on experience. You will also want to take as many of the Splunk training classes as you can afford or justify – they are excellent and essential for obtaining a more rounded knowledge base and those oh-so-important certifications.
The list of topics and documentation links provided offer good coverage for much of the Splunk landscape; I suggest you at least browse through these just to make yourself aware of all of the subjects – the real learning happens when you really need to look up and use a feature or configuration setting. After a while, it all starts to gel together and your confidence and efficiency both climb dramatically. Check...