The tree looks very pale and ghostly as the name suggests; the wood is a dull grey and the leaves are almost white. Like others, the logs provide 4x wooden planks. The tree can also make a Ghostwood Door and has its own set of tools.
A Ghostwood tree growing on tainted soil in the Overworld
The tree is found in the Nether growing on the ground. It can be transplanted to the Overworld as long as you place a Tainted Soil or Netherrack block and then place the sapling on these specific blocks. You can place the sapling on regular dirt, but it won't grow unless it's on the Nether blocks.
Like all trees, it can be forced to grow with Bone Meal.