Macbook pro internal HD not detected
You are not seeing the drive because has no more partition on it.  What you have done is written every sector, including the super important ones like the partition table, with random numbers.

When you boot USB (I am assuming you are booting an OS X installer off of USB), you need to launch Disk Utility.  It will be under the "Tools" menu.  Partition your disk with GUID partition map and reinstall OS X.