Here are some good resources to get you started:
SQL Server 2008: New Performance Monitoring and Troubleshooting Using Management Studio
Performance Monitoring with SQL Server 2008
SQL Server 2008 Performance and Scalability Technologies
Suprotim has received the prestigous Microsoft MVP award for nine times in a row now. In a professional capacity, he is the CEO of A2Z Knowledge Visuals Pvt Ltd, a digital group that represents premium web sites and digital publications comprising of Professional web, windows, mobile and cloud developers, technical managers, and architects.