Here's a great exercise - use current TV commercials!
Really listen to the commercials on your TV or radio. When you find a good commercial you like, try to parrot the VO actor who is speaking the lines. You'll be repeating the words, of course, but also try to copy, as exactly as you can, the nuances, the tone, the inflections he or she uses, and the musicality.
Then mute or turn off the TV or radio and grab any random bit of text, such as an ad in a piece of mail or magazine. Try to bring the new tone and vocal patterns you've been copying to these new words. You will be using the style you've been mimicking with this new material.
This will really start to train your ear and attune you to what is currently “hot” in the advertising world. And it gets you practicing, reading aloud, and using your voice in new ways.
And it's fun! Enjoy!