Text-to-Speech Just type in the word you want to practise and listen to the correct pronunciation. Be sure to choose the male or female voice. You can also alter the speed of the voice you hear to get used to fast (or slow) speech, too.
Phonetics: The Sounds of American English This site has videos and animations for each sound in English. You can watch someone pronounce each sound, and you watch how your mouth, lips and tongue should move in an animation.
English Pronunciation Practice This is a section of an excellent website for ESL students called ManyThings. On this page, I particularly like the Listen and Repeat Machine. Good pronunciation is not only about saying the individual sounds correctly (although that is, of course, important), but also about having natural intonation and rhythm over whole phrases and sentences.
EASE – Presentations This is another of the sites prepared by The University of Warwick to help you learn academic study skills. The first unit is available online and if you want the others which are on CD-ROMs, ask your teacher.
Making an academic presentation This is a video introduction by a Senior Tutor at the University of Portsmouth on how to make a presentation. You can watch it in a small window in the site, click it to watch it on a full screen, or download it to your computer.