Im going to the wwe live event in Oshawa on May 3rd and Im just wondering how long they are

depends on the event. Raw will go 3-4 hours. NXT will go a couple of hours.. Regular house show will usually go 2 or 3 depending..

3 hours

I went to a RAW supershow here in St. Louis a couple years ago and it lasted 4 - 4 1/2 hours

+/- 3 hours