Like many others I became interested in CNC machining and decided to purchase a Grizzly G0704 benchtop mill and convert it to CNC. I purchased a copy of Hoss's Plans, the machine and went to work. I had basic hand tools, a cheap small drill press and no knowledge of machining.
7 months later and $8000 lighter I'm basically finished and while a lot of the conversion is pretty standard there are some things I did differently from most that I haven't seen documented anywhere before. I figure someone down the road will be grateful for the documentation and tips and tricks.
If you have the same dream I did, to have a metal cutting robot in your basement, but have no machining experience the only advice I can give is it's possible. You will crash tools, your vise will get dinged, it's all part of the learning process. Try to buy the cheap tooling first so when you destroy it and buy nice tooling it will stay nice.