Helpful Resources for Pronunciation

Stress, Rhythm & Intonation (Youtube Videos)

• Stress and Rhythm Practice (Highly Recommented)
• Vowel Changes in Stressed and Unstressed Syllables (Highly Recommended)
• Intonation Practice (Recommented)

Stress, Rhythm & Intonation (Articles)

• Intonation and Stress in English
• Sound Scripting (Stressing Practice with Native Speaker Example)

Accent Comparison Practice: Try reading/recording the following script yourself first and compare to the following MP3 files:

"Please call Stella.  Ask her to bring these things with her from the store:  Six spoons of fresh snow peas, five thick slabs of blue cheese, and maybe a snack for her brother Bob.  We also need a small plastic snake and a big toy frog for the kids.  She can scoop these things into three red bags, and we will go meet her Wednesday at the train station."

• New York Accent MP3 with Script
• Chinese (Mandarin) Accent MP3 with Script
• Korean Accent MP3 with Script

Note: For more variety of accent samples for other speakers, go to The Speech Accent Archive

Commonly Mispronunced Consonants and Vowels (Youtube Videos)

• /v/ vs /w/ (e.g. vine vs. wine)
• /l/ vs /r/ (e.g. lice vs. rice)
• 'th' /θ/ & /ð/ vs. /s/ & /z/ (e.g. sink vs. think, breathe vs. breeze) 
• 'th' /θ/ & /ð/ vs. / t / & / d / (e.g., thank vs. tank, thorn vs. torn)
• Diphthongs (gliding vowels such as [aɪ̯], [aʊ̯], [eɪ̯], [oʊ̯])
• /æ/ vs /e/ (e.g. bad vs. bed)
• Long 'e' vs. short 'i' (e.g. leave vs. live)

Books
American Accent Training by Ann Cook, Barron's