If you've got the perfect bit of audio, but it just so happens to be in the wrong key, maybe you need zplane's reTune.
This new plugin enables you to access the pitch content of your audio, giving you the option to map the 'input pitch' to any other pitch of the chromatic scale. So, for example, you can retune a phrase to a completely new key; if you don't know the key of your input audio, reTune will estimate it for you.
You can also use the plugin in more creative ways and as a pitch correction tool that pitches to the nearest semitone. You can adjust the sensitivity of the pitch correction, the treatment of the transients and the smoothing of the pitch contours.
reTune is available now in VST/AU/AAX formats for PC and Mac priced at $199/€149. You can download a demo if you want to try before you buy. Find out more on the zplane website.