I am not a stickler for how people spell my name, but I figure I'll get it stated publicly at least once.
My name is Ricardo. People have asked, "Do you mind if I call you Ricardo?" No, I don't. It's my name. My name is not Richard, and I will be annoyed if you call me Richard or Rich. My name is certainly not Richardo, and I will be very annoyed if you call me that or address mail to me that way. It genuinely annoys me.
I almost never write my own name, except for my signature or my initials. When I do, I write "Rik." Many of my friends call me that. I never write Rick or Ric. Sometimes people say, "But there's no 'k' in Ricardo!" Well, there's no "k" in Richard, either, and people write "Rick" for Richard. I spell it R-I-K, and if you're going to call me by that name, you should, too.
I doesn't bug me when people spell it Ric or Rick, but I imagine people would rather spell it the way I intend, not some other way. (It's strange, to me, that people usually default to Ric.)
I also respond to Rico and RJ, by the way.