I live in AK, all 32 years of my life.
Like any place it has it has it's ups and down. Like Yeag said, weed on the state level is, for the most part, legal to posses in the home. I think it's 2 ounces or something like that. It's illegal to buy, sell and grow. I also think the punishment is light for growing up to 24-25 plants. I can't quote the law, but in reality, it's a slap on the wrist.
Federal law is the same as any other state, illegal illegal and... Illegal.
As for specifics on Sitka, I can't help you there... I do know that's just too small and too remote for my taste. Home life in the "big" city has been stressing me out more and more over the years as the pop grows, but as the saying goes, if you can't stand the heat, get an AC.. or an AK. something like that.
I've lived all over the state in my short existence, I'd consider moving to the "Valley" (Wasilla, Palmer) if the good jobs that I'm qualified for were out there. A boat load of people commute (about 40-50 miles one way) each day from those City's and with the price of gas... eh, I'm not an import driver, and I get road rage like a sumbitch, so I can't convince myself or my significant other to move out there.
You can hit me up with other questions if you'd like, I can try to answer what I know, or BS what I don't. You'd be able to tell the difference.