How to use index to optimize query performance in sql server

Refer:
Defining Indexes with SQL Server 2005[^]
This article deals with:
-Query Optimizer
-Creating an Index
-Creating Unique Index
-Creating Clustered Index
-Creating Full-Text Index
-Changing properties of Index
-Renaming an Index
-Deleting an Index
-Specifying Fill factor of Index
-Create XML Index
-Delete XML Index
-Advantages of Indexing
-Disadvantages of Indexing
-Guidelines for Indexing

SQL Server Indexed Views - Speed Up Your Select Queries: Part 1[^] - An introduction to SQL Server Indexed Views.

Speeding up database access - Part 1: Missing indexes[^]- And series of 8 articles.