Karen Traviss, 2004-2009
Yes, its at the top of both my games and books list. That's just how good this series is. The RC books give us insight to the beginnings and the training of the clone commandos, and focuses on Omega Squad, whose ranks consist of clones from other squads whose original members were all killed off.
What really makes this series awesome is the amount of work Traviss has put into it. She develops a language (Mando'an, I mostly just remember the swears) and establishes the Mandalorian culture that I've come to love (remember who my favorite character is). The last novel features their transition into the Imperial Commandos, serving the newly formed Galactic Empire.
Unfortunately, due to the then-airing Clone Wars TV series establishing the Mandalorians as pacifists and rendering Traviss' story non-canon, she never wrote her final novel, leaving the series completely open-ended (she did reveal the ending in a fan email). Cheer up Karen, EVERYTHING is non-canon now. You'd better blow my mind, J.J. Abrams, you aruetii. <- (Mandalorian term that means outsider)