I've searched config parsing libraries for my project recently and found these libraries:
http://www.hyperrealm.com/libconfig/ - small but powerfull and easy-to-use library,
examples of using are in the source package and here
http://pocoproject.org/docs/Poco.Util.PropertyFileConfiguration.html - a part of pocoproject. You can use abstraction in your code and behind that use various supported implementations (ini files, Xml configs, even environment variables)