Camarena-Williams made her second consecutive Olympic team by winning the shot put with a throw of 62-10 1/2.
Michelle Carter and Tia Brooks finished second and third to become a part of the U.S. squad that will compete next month at the London Games.
Coburn then dominated on her way to victory in the 3,000-meter steeplechase. She outdistanced runner-up Bridget Franek in the time of 9:32.78, capturing the race by almost 3 seconds.
Coburn's University of Colorado teammate Shalaya Kipp finished third in 9:35.73 and will be going to London. The women's steeplechase will be held for only the second time at the Olympics.
In preliminary action, defending Olympic gold medalist Angelo Taylor led qualifying into the finals of the 400-meter hurdles with a clocking of 48.77.
The United States swept the medals in the event at the Beijing Olympics, with Kerron Clement winning the silver and Bershawn Jackson the bronze. Jackson had the second-fastest qualifying time Friday with a 48.83 and Clement was third in 49.04.
In qualifying for the women's 200-meter finals, Sanya Richards-Ross led the way in 22.15, followed by Allyson Felix and Jeneba Tarmoh.
Felix was the silver medal winner in Beijing.
After the opening day of the heptathlon, Hyleas Fountain led the competition with 3,948 points -- 151 more than Sharon Day. Fountain is hoping to improve on the silver medal she won in China four years ago.