There's the gay-owned Sunseeker hotel, complete with communal hottub to watch the sunset from. I've never stayed there, so I can't comment on how it is, but you'd probably meet some other travelers: http://www.mauisunseeker.com/

You can also check out the events section of http://www.mauigayinfo.com/ to see what's going on.

And as others have mentioned, there's usually guys hanging out on the far side of Little Beach pretty much every day.

Have fun!