I am a new grad too and worked in the ER for a month now. So far, I have seen a lot of: foley catheters, starting IVs, bladder scans, splinting, CPR, suctioning, NG tubes, suturing and wound dressings. The thing about the ER is that every day is different so some of the other new grads in my program may have seen completely difficult skills. It just depends on what walks through the door.
If I could go back and review before starting work, I would use my health assessment book to look over focused assessments and electrolyte imbalances. It is amazing how wacky some patients' electrolytes can be when they first show up at the hospital!
Finally, looks over your medications. Common drugs I deal with on a daily basis are morphine, dilaudid, ativan, toradol, metoprolol, nitroglyerine, acetaminophen, furosemide, ibuprofen, zofran, epinephrine, adenosine, atropine, rocephin, lidocaine, magnesium sulfate, benadryl, diazepam, phenergine, zosyn, reglan, plavix, flagyl and protonix. Consider why and when they are used, contraindications, side effects and parameters.
I had a 12 today and that's what I can think of off the top of my head.