If you search the forums, you might be able to find threads on topics like, "things I wish I had known when starting graduate school" and "how to study in graduate school" which could be helpful.
Short answer: yes, it's normal to feel overwhelmed. Heck, I'm on post-doc and I'm still overwhelmed on a near-daily basis by the amount of information I'm seemingly expected and/or that's available to know.
I'd suggest taking it on just like you would any other large task--break it up into smaller, manageable parts with realistic goals, study frequently and at a constant rate (rather than cramming), delegate responsibly (e.g., if there's too much reading for any one person to possibly handle, get together with a few classmates, have everyone be responsible for a few articles, and then meet to summarize key points and information for one another), etc. Related to that last suggestion, actively reviewing material with other folks can be particularly helpful when you force yourself to try and teach it to them, as that's what can really lead to you increasing your understanding of what you know and shedding light on all the areas that you don't know.
