To store the configuration information in SharePoint site you can use the AppSettings
I have created a project (Property Bag Settings) on codeplex that helps you to manage configuration information in SharePoint at all levels, including the:
• Web Application
• Site Collection
The Property Bag Settings can store any metadata as Key-Value pairs such as connection strings, server names, file paths, and other miscellaneous settings needed by a SharePoint application to perform work.
You can download the source code from codeplex here