Hi,
I'm a good carpenter.  I won't have any problems putting together the cabinet.  I'm also an electronics technician.  Connecting all the buttons, joysticks and keyboard interfaces won't be a problem.
The problem is the software.  
I just spent an hour trying to figure out how to download MAME and a front end, and I couldn't do it.  
I'm not computer illiterate.  I use a computer every day for work.  Granted, I rarely have to install programs at work, but when the directions told me to go to a command line prompt and enter C\program files\mame0101b  mame -      I understood what to do.
So, why can't I simply make this work?  
I downloaded a couple different MAME versions 101 and 67b for windows.  I also downloaded a front end from here:
http://www.mameworld.net/mameclassic/When I tried to run the front end program, it gets to a menu where none of the file locations are found, even when I told it to use the defaults.
When I tried to run mame101 from the command line, it won't run without a ROM installed.  I tried to find a ROM for good old fashioned space invaders, but when I googled "ROM space invaders" I couldn't find what I was looking for.
Maybe I should find another hobby instead?  I'm 36 years old, it's possible that I just don't know enough about what I'm doing here.  
Frustratingly,
Steve