It depends on what you want to do with the oils. Whether you want them for healing purposes, holistic purposes, fragrance/beauty, etc.
I've created a few starter's kits for people just like you who don't know where to start: http://www.aromalchemy.com/aromatherapy/starterskits.html
If you don't want an entire "kit" then simply review my summary page about oils... http://www.aromalchemy.com/aromatherapy/ouroils.html
This page gives a brief description of each oil's properties...this way you can pick and choose which ones best meet your specific needs. If you click on the "learn more" link for each oil, you'll get a page which further details the oils' properties and also provides sample blends using that oil.