Buy some classic game collections (for PC or if you can read the DVD's from PS2, go for those versions) and distil the roms from there. Sometimes you need like Filejuicer or so, or sometimes its just a matter of renaming certain files to romname.zip. Watch out that most of these packs run an old version of MAME and version 0.129 wont work on them. It's probably against the EULA (what's legit about those texts anyway?) of those discs, but hey, you should never double click the installer on the DVD's as it installs tons of copy-protection crap and malware, and thus you never had chance to read and accept the EULA (Its shown in the regular installation proces). So it's pretty legal. You pay to own the roms, you just rename them and put them in a different folder as intended. Who's gonna bleed on you about that?
How do you post a link to Youtube that does not shop up immediately.