Would you recoomend this project?
A generic type QuadTree implementation in C# for use with XNA. This QuadTree can store any object that implements the interface IHasRectangle. This provides a means of accessing objects in a virtual space very quickly.
Development moved to: https://bitbucket.org/C3/quadtree/
You can download file releases of QuadTree project from List of release files
System RequirementsOperating System: Windows 7, Windows NT/2000, Windows Vista, Windows XP, Microsoft Xbox 360
Date: 2012-01-18, Size: 301614
List of release files