Sharky - I've never known anyone who thinks it's weird to say "hey guys," even when referring to girls, but everyone feels the need to let everyone else know that they're used to it even though others might thing it's weird. And that's across - NY, PA, OR, WV, NC, FL, OH, WA, CA, and ON Canada at least, I've also heard it used regularly in British and Australian English. Last time someone made a big deal about how weird it was they said "hey guys" to girls I felt provoked to violence. It has actively begun to p*ss me off. Not targeting you or anything, just saying. Where the heck are these damn "areas" people talk about? Who thinks it's weird to call a group of people "guys" regardless of gender? To people who speak English as a second language, that's it, and even in Spanish you use male terms to refer to a group of mixed gender. /rant.
Never heard "bud" or "buddy" used to refer to a girl casually before, unless it's a teasing friend thing. I might have heard girls calling each other bud before, like they sometimes call each other f*ggots. When I hear "buddy" from a guy, I know I'm passing. And that's Western PA/Upstate NY that I'm used to. So that's cool, congrats!