This site offers annotated texts of all of Shakespeare's sonnets, and several ways to navigate through the sonnets:

• Table of Contents: Lists all 154 of Shakespeare's sonnets, together with the first line of each sonnet, and a short summary of the sonnet. Each entry in the list is a link to the sonnet.
• Most Popular: Here's what Google and Bing think.
• Search Page: Search for any word or phrase which appears in a Shakespearean sonnet.
• Thematic Index: Search for sonnets about the Fair Youth, the Dark Lady, the Immortality of Poetry, etc.
• Unique Sonnets: The one with only 12 lines; the one with 15 lines; etc.
• Sonnets for Lovers: My top ten.