Here's a site that has a list of some environmental training courses: http://www.training-classes.com/learn/_k/e/n/v/environmental_design/
There are many places one can learn about interior design online. You can try blogs on interior design, forums on interior design, or even sites that specialize in selling interior design products.
You can learn graphic design from a variety of sources. There are online courses, community colleges and normal colleges. All you need is a school which offers commercial art and graphic design courses.
There are many places where one can go and enroll in advanced design courses. One can try local colleges for information on design courses. If you have internet access then the best website would be ASTD as they offer online courses.
One can learn more about office interior design by taking online courses from interior design schools such as The Art Institutes, Century or RISD. One can also learn more on office interior design by looking through online magazines such as Contract Design and Architectural Digest.
There are many websites in which one can learn about principles of design. Goshen and Web Design offer online courses on it. There are also many books that one can check out from the library that can be used.
Many places offer courses in online design- the best place to look for such courses are through college websites or through advertisements in the local news. There are also websites that offer information on online design.
One can learn to design their own home from a variety of different resources. One could take design courses at a local college or one could watch tutorials online to help them learn to design their own home.
There are many interior design programs, such as the Academy of Art programs that are online. However most design programs set for interior design is better to learn in person rather than just online.
To learn more about environmental services online you can visit the NH Department of Environmental Services which is considered the official site of Environmental services.
There are many schools that offer free online game design courses. The MIT OpenCourseWare allows students to learn about game development and designs for free.
There are many places where one can learn more about website hosting and design. Once can try a local community college, or even forums and online courses dedicated to the subject.
To learn about retail design you can go to college and take some courses on design. You could also get an internship and you could learn while you work.