Well, there's not automatic "make me sound like somebody else" option, otherwise I could have a great career as a vocalist!
Seriously, your best bet is to try and imitate the style you want--phrasing, pronunciation, etc.. as best as you can. Then you can use tools like the Pitch Changer in Effects/Time and pitch to alter your voice into the same vocal range as the person you're imitating. Also, creative use of EQ can make you sound quite different. Finally, listen carefully to the recording you're trying to imitate and try to copy things like the amount of reverb used, compression, etc.