Someone else did mention the June Tailor Shape Cut ruler...that is a tool I would NOT want to be without...such a time saver. Everyone has listed so many necessary tools. Start with the basics, and then see what other tools you may need. A longer ruler (6x24) a shorter ruler (maybe 4-1/2x12-1/2) a square ruler (6x6) would be the minimum of rulers that would be helpful for a new quilter. A good seam ripper is useful (I like the Clover one). A good pair of scissors, and a small snips. Of course a rotary cutting board and cutter.
Have fun!