Weather Weenies (that's their real name) is one such site I came across. Steve Blum and Chad Alcares are the chasers that run this site, and mainly chase in Nebraska, Kansas, and Northern Oklahoma. They do journey to other regions, and people can follow their progress on a map within their site.
Remember this is just one site about storm chasers. If you find one, put it in the comments section below.
Note that storm chasing is not an exact science and can be VERY dangerous. However, there are some groups that offer storm chasing tours. This is just one group that I found.