Guys, I would like to recommend you a page here. Shame on me that I somehow missed it.
Maybe somebody from you knows this site already. I've helped a user here and created a screenshot
but forgot to recommend this page too. Original Article here:
MAME-0-207-ROMs-sooner-arcade-mess-.htm
I would like to make up for it now.
This page provides information about the MAME roms. You can search for the zipname (ie machine or game xml tag)
or and that I find interesting for a sha1 value someone maybe has and does not know to which rome it belongs.
The site is a very nice optical (for us humans readable version of the XML data from the MAME) version than just
a text editor like Notepad ++.
It helps me a lot. Give it a try.
Cheers