I don't think I've seen an inclusive guide that made things super easy. The whole idea going into it is you're building something unique. The guide you linked seemed pretty good, just understand where you can deviate and figure out what you want your arcade to have. I'm working on my first build now and honestly I just kinda research problems as they come up. Some problems I recommend looking into though, to help kinda focus your research:
-how are you gonna set your computer into the cabinet,
-what speakers are you going with,
-what buttons/joysticks/devices does your control panel need to play every game you want to play,
-what software frontend do you wanna use(I recommend trying a few out),
-what art/marquee are you gonna use(Or if you want to create, then how are you gonna make or commission the art),
-t molding or no,
-coin door or no,
-how are you gonna light the marquee(light bulbs, flourescents, led),
-what kind of tv will you be using(crt takes extra work to get working on pc),
-how are you gonna wire your buttons to your computer(you can buy premade control panels, wire up a keyboard to buttons, or buy a controller like an ipac).
-You can use a smart strip to power everything on at once. Set the pc as the main outlet.
-If you wanna go led for your marquee light and aren't terrific with wiring, these are wide leds and they can be wired into the molex connector off your power supply.
http://groovygamegear.com/webstore/index.php?main_page=product_info&products_id=307Sorry it's not what you're looking for, but hopefully it helps a little.