Oh well, what could I add to James' advices? Try this out: http://www.youtube.com/watch?v=jy4A8fpOHcc She speaks clearly and articulates well. If you happen to like her music you will have loads of opportunities to practice your English.

The best way to improve oral english skill is to use it. It is almost training your mouth to produce new movements and sounds. Start slow. I would start developing listening skills for english language. Listen to english dialogue in popular media; radio, television. Find a voice you like listening to. Start reading things out loud in english. Practice with a native speaker. I always tell people to read aloud, what they just wrote. Does it sound like the english you heard before from your listening activity or from your interaction with native speaker? Record yourself speaking english. Sing a song, read from a book. Listen to yourself. Where do you slow down? Do you pause enough or too much. Do you slur words together or accent on certain syllables. Practice words that are giving you trouble. Try speaking in rhymes or tongue twisters. This is how some english actors get better at elocution or speaking in public. It takes practice, but it will be worth the effort.