You can put your home address, I don't think it is intended only for businesses, I guess is in the same stride with Visual Studio Shell to try and attract also the opensource community.
From the License documentation
A number of free development tools are also available, including
Visual Studio Express 2012 for Windows 8, Visual Studio Express 2012
for Web, and Visual Studio Express 2012 for Windows Desktop. These
tools provide a subset of the functionality available in Visual Studio
Professional 2012 and are specific to writing applications targeting
these platforms. Each of these Visual Studio Express 2012 products is
licensed per user and subject to the use terms included with the
product. Visual Studio Express can be used to build production
So it is free, but you are right you need to register after all. Try to put None for the organization, and 0 for numbers of employees. Business address, fill your address or whatever address you think is relevant maybe school its your choice an privacy.