Yup, I mainly used Anesthesia Secrets and Anesthesia Made Easy. I found the latter to be extremely useful as a quick reference to have with me throughout the day.
Search the anesthesia forum - I asked this question when I was doing an anesthesia elective as well. I used anesthesia secrets and anesthesia made easy. Also, use Procedures Consult (we have access through our library) to read about blocks, epidurals, spinals, c-lines, a-lines, etc. The more prepared you are, the more likely the attending will let you try some stuff. I'd focus mostly on getting the feel for all the equipment first (oxygen, suction, ECG, pulse ox, IV, gas, anesthesia cart) before you worry about minutiae like MOA of the volatiles.