Hello Ashley!
Yes, you should definitely wait for your textbook before you take the exam. As loribe stated, the textbook goes into way more detail and contains A LOT more information. The study guides just kind of give the basics of each lesson/chapter. WAIT FOR THE TEXTBOOK! LOL.
It usually takes about 7-10 business days to receive your books through the mail. You can check out this link about Book Shipments here: Book Shipments FAQ. You also have the option of having all your materials sent at once; check out this link on how to do that: How can I receive all my semester course materials in one shipment?
I hope this helps! Good Luck!