I recently upgraded my Ubuntu 12.10 to Ubuntu 13.04 and the nautilus was also upgraded. Now the problem is when creating new file or blank file using right click, there is no option other than creation of new folder.
The solution is just simple, open terminal, go to ~/Templates/ folder by running
cd ~/Templates
Then run
touch New
Or whatever file you want to create. Then open nautilus and right click, now you will see the option for adding new file.