Celemony Software Melodyne, €349-€699
It might not be the most famous pitch-correction tool, but it may very well be the most sophisticated. Melodyne can examine your recordings, extract the timing and the pitch and make them available to you on a timeline-style grid. You can adjust the timing and pitch of each syllable, even creating complex harmonies from monotone lines. Amazing.
Read Celemony Software Melodyne Editor review
Antares Auto-Tune, $129-$399
The name has become synonymous with pitch correction and outre pitchshifting: Auto-Tune, when used tastefully, is a miraculous time-saver for the desktop producer, and when used in a more over-the-top fashion, it can be a hit-maker.
Read Antares Auto-Tune Evo review
GVST GSnap, Free
If you're on a PC and on a budget, you might want to avail yourself of the free GSnap VST plug-in from GVST. It can handle all of the basics, from subtle correction to more outlandish Auto-Tune-like warbles. You can tell it which notes to ignore and which ones to fix, and thanks to the built-in gate, it'll even ignore any background noise that crops up during the quiet bits.
Find out more about GVST GSnap
Roland V-Vocal, N/A
This clever little fellow is bundled with the Studio and Producer Editions of Sonar. It provides pitch and time correction along with full malleability of your track, and will be very familiar to users of Roland's VariOS system. It's easy to use and great fun, too.
Read Cakewalk Sonar X1 review