Since folks have asked, lets take a break from the gear parts of first aid, and talk for a minute about where to learn how to use all the gear you've acquired. There are two nationally available training resources I can recommend without reservation.
The first is the American Red Cross. They set the curriculum that most other trainers teach to. I've personally taken a number of their courses, and they teach a variety of good information.
The second is National Safety Council. They taught my most recent first aid course. The curriculum was solid, well-presented, and easy to understand. They also have online options available if conflicts prevent classroom training.
There are other options as well. Local volunteer emergency groups (locally, we call them Community Emergency Response Teams) often host training for free or reduced fees. They're also a valuable resource and affiliation in general for preppers. Your local city hall or fire department can provide information about such groups in your area.
Many employers also offer first aid and CPR training, frequently on the company's dime. Your employers Human Resources or Safety department can tell you about any programs your company has. Any time you can get someone else to pay for training, it's an opportunity you should at least consider.
If anyone has any other good nationwide training resources, please share them in the comments.