To answer you question, yes there are sailing sims out there. I used to tinker with some of them a few years back. My parents live aboard these days, I kinda grew up on a saiboat. I'm not sure if there any that are native to Linux but I'll take a look around. You might want to take a look at these in the meantime...
These are all Windows based, but maybe they'll work with WINE.
Here's one with more links than I care to list out for you. Alot of intersting sites.
The Mother of all maritime links