Contact management class library

Is there a good and complete class library for contact management around? I've looked around on the internet but can't seem to find one. One of the first 'real' programs I had to write during my education was a .NET application to manage contacts, an addressbook. Add, edit and remove people, with addresses, phone numbers, etc. These people could belong to a company which also had an address, and so on. It was fairly simple.
I'm on to a bigger project now, and need more than people and companies. I'll need all sorts of organisations, different types of people, etc. What strikes me as odd is that I couldn't find a class library that allready had these features, and focused solely on this scope: contact management and contact management alone.
I can imagine hoards of developers and student-programmers build a few administrative applications in their lives, so why is there no reusable class library to manage this? It's practically always the same: person has address, company has people, company has address, address has a street, number, country, etc. It shouldn't even be a very big class library.
So I plan to release my class library out into the wild when it's finished. So that not only I, but also others can skip the part of developing the zillionth contact management library and focus on the specific work of the job.
The library will probably not fit everyone's need but inheritance and open source should be able to solve that.