This is a good guy to follow, I wish he'd fight for position instead of rolling over, but he puts on a good show for the NiS Fixed Series. This is his YouTube Channel
It depends on the series. Most guys race in the Sprint Cup series (Fixed and Open) and those races are half of the real life races. So if a real life race has 400 lap, the iRacing race will have 200 laps, like Richmond this past weekend. Then you have series like Street Stock, Late Model, Modifieds, Legends. Those can be anywhere from half an hour to an hour.