Is there a C++ library that enables reading of .tga and .blp image formats on Windows?
For Targa (.tga) files, the FreeImage library may be useful.
I recommend using SOIL. I found it to be by far the easiest way of loading and saving texture to and from OpenGL. The last update was in 2008, though. It still works fine, but some people like to steer away from "old" software.