Raw Land Help!

[Megan Aldridge]

Good Afternoon!  I am looking at a deal on a piece of raw land.  I drove past and it's in a decent residential area - as far as I can tell someone must have planned on building on it at some point, but then the deal fell through or something, I think.  Here's my question:

It's covered in mature trees and weeds (so not cleared at all).  Who do I contact about finding out if this land is good to build on?  I certainly don't want to buy it and find out I can't build a house on it.  

Thanks!