Microsoft's TechNet has released a useful set of step-by-step guides to help people learn, understand, plan, deploy, configure and maintain Active Directory infrastructures on Windows 2003 domains.

From the AD Step-by-Step Guides page, the following individual titles are available (see the main page for more information about each):

• Installing Windows Server 2003 as a Domain Controller
• Installing a Windows XP Professional Workstation and Connecting It to a Domain
• Setting Up Additional Domain Controllers
• Managing Active Directory
• Understanding the Group Policy Feature Set
• Using the Group Policy Management Console
• Enforcing Strong Password Policies
• Using the Delegation of Control Wizard
• User Data Management and User Settings Management through Group Policy
• Configuring a Dial-Up Remote Access Server
• Building a Site-to-Site Virtual Private Network Connection
• Using the Encrypting File System
• Digitally Signed and Encrypted E-Mail
• Active Directory Sites and Services
• Active Directory Bulk Import and Export