This is what I use for my oils and I love it! It'll hold 5 ml bottles and 15ml bottles and even your roll-ons. Essential Oils Presentation Case and Portfolio 64
The elastic bands that hold the oils can be placed above the names on the labels so you can easily see which oil you might be looking for. You can see mine in the teeny tiny picture on my homepage.
Mine isn't quite full but it is getting there! Oh Oils!