I am a C and C++ programmer, though I am more of a userspace/desktop applications programmer. I've done a small bit of tinkering at kernel level, but not a lot. I followed a couple of tutorials on how to develop a kernel module, and tried debugging a couple of modules, but I've never gone as far as joining any mailing lists or anything.
However, the link shared by Stan/Atanere (the official docs for the Linux kernel project) will tell you all you'll need to know and more!