I need help with Active Directory--Windows 2K Server

Question

I am an extremely novice programmer who decided to jump into the deep and become a C# developer. I am now in charge of developing a series of services that run against an AD. I need help creating a user, adding a user to a group, removing a user from a group, reseting user passwords, etc... If anyone can please help me with some of this code, I'll be eternally grateful. Who knows; maybe one day I'll return the favor. Thanks Hector