NASCAR, which stands for the National Association for Stock Car Auto Racing, was founded by Bill France in 1947, and continues to be family owned. It is the largest sanctioning stock car racing body in the US. The three largest NASCAR races are the National Series, the Camping World Truck Series, and the Sprint Cup Series. If you want to find fast car videos, NASCAR is one place to look.
Safety has always been an issue with race car driving, not surprisingly. NASCAR often only adopts safety measure mandates years after they are developed, in response to injuries or fatalities that could have been prevented if they had acted sooner.
For example, Smokey Yunick proposed the SAFER Barrier impact absorber back in the 1970s, but his idea was thought to be unnecessary and expensive, and NASCAR did not follow through until much later. Implementation of all drivers to have a throttle kill switch was slow, and did not become mandated until after the death of Adam Petty.
Some critics question the way the family handles NASCAR business, and suspects them of manipulating race outcomes not in order to make the race safer, but rather, to encourage closer racing. When you look at fast car videos of NASCAR, this criticism does seem valid, owing to the way they decide to flag the drivers. And it is easy to see how a close race would make viewers more engaged than when there is a clear winner. It makes for better videos of fast cars.
There are a lot of fast car videos online and there are many ways to access them. NASCAR races are but one example of fast cars. There are a number of racing bodies, as well as a fair amount of amateurs posting their own fast cars videos.