So, being new to CNC machining (looking at acquiring a Tree mill to play with, ref Tree forum...) I realize more and more I don't know hardly anything. So, I figure I'll put the problem solving/self teaching ability that was the best thing I got out of my degree and learn. Without asking a million newbie questions, I'll perhaps avoid most of them hopefully through someone's answer to this one:

Anyone know a really informative website I can check out that would help me develop a thorough understanding of the intricacies of CNC? (Sans machine and code to play with). For example, I'd like to learn more about the process to go from a 3D design to G-Code (or whatever it takes to actually run a machine), i.e "post-processors" and the like... Need to know what is possible in programming, i.e. you can write code on a desktop and load it on your mill, right?? (I'm sure it's and obvious answer... just want to know for sure)

Have lots of manual experience, zero CNC... So I do mean "from the ground up!"

Thanks in advance! Pointing to old threads that answer the same question is great!