I don't think Darren Modok was featured in the comics. Usually, characters like this don't just pop up without notice or a lot of buzz among comic fans.
One of the main themes is probably loyalty. Kirk McGarvey likely has to deal with who he can trust and who is loyal to him in the complex situations he faces. Another could be survival, as he is presumably in dangerous situations where his life is at stake.
Second - hand bookstores can also be a good option. Sometimes they have rare or out - of - print books that you might not find elsewhere. It's worth checking them out if you're having trouble finding the Kirk McGarvey novels in other places. Plus, it's a great way to discover other interesting books while you're there.
Sure. 'The Cardinal of the Kremlin' by Tom Clancy is a great one. It features intense espionage and a complex plot. Another could be 'The Hunt for Red October' which also has elements that might be similar to what Kirk McGarvey novels could potentially offer in terms of suspense and international intrigue.