User blog comment:Roranoa zoro/Wikia founders/@comment-3080486-20110529092525/@comment-2093602-20110529101747

That's indeed a good method. It won't work when the founder didn't edit his front page, but that probably doesn't happen very often.

Another easy way that works on newer wikis is to look at the very first contribution of User:Sannse or User:Sarah Manley if it's not there (or User:Avatar on german wikis). Welcome messages are signed under their name :)

Doesn't work on older wikis though (with some luck you may find the founder in the contribs of User:Angela). It doesn't work when the founder deleted his own talk page either.

So in the end, your method is probably the best one in almost all cases.