After the initial anti-trans-fats craze of the 1990's, nearly everyone forgot about the danger for several years. Adequate information was lacking, bold, seemingly outlandish couldn't be backed by hard data, and the general consensus seemed to be that even though trans-fats were almost certainly not good for us, it was difficult to tell just how much damage they were causing or how much was in our food.
However, an eventual push for greater regulation and more restrictive legislation has gradually pushed trans-fats out. First, manufacturers were required to indicate the amount of trans-fats present in an item on the packaging. Then, states and smaller governments began banning their use in restaurants. Finally, in 2013 the FDA declared their use use generally unsafe, and began the process of banning them outright.
That legislative push was successful, and recently the ban went through; by 2018 all manufacturers are required to remove any and all trans-fats from their products. In the mean time, though, many of the food products frequently found in kitchens will still contain them.
To avoid consuming trans fats entirely, it's best to always check the label before buying, but there are several items which are known to have them in abundance. Keep an eye on microwave popcorn, frozen pizza, margarine, canned frosting, coffee creamer, and pre-packaged baked goods. Even though there is a ban on the way, it's best to be careful and check the label!