How do you fabricate an engine mount?

I am looking to completely remodel a 2000 Mitsubishi Eclipse with all new parts from the ground up. My first look is at an engine and transmission. I was thinking of purchasing a high-performance V8 engine to throw into the eclipse, but that model only seems to have a V6, so I was wondering what I would use for it, such as a different company's V8 and mount it in my eclipse, or if i need to go to a custom auto shop for them to make a custom engine. Either way, I have been reading that to do it, you must "fabricate" an engine mount for it to fit. What exactly does that mean, how do you do it, and is it possible for the general person to accomplish?