Thank you in anticipation of your kindness and gentleness. Sorry to disappoint you Richard your in the wrong place for that sort of treatment

Seriously, you will get a lot of help from people on the forum, first sort of thing to do is think about what sort of size machine you would need, what materials you would want to be able to machine & what sort of budget you have.
As for buying a machine versus manufacturing it yourself then it comes down to how quickly you want to be using it, if it's for business use then sometimes better to buy as your up & running almost straight away but if it's just for hobby use then building is quite often a better option as you have the experience and reward that goes along with DIY plus it makes maintaining it a bit easier as you will know the machine & how it works. Have a look through some of the build logs & it will give you a good idea of what is involved in building your own machine.