Hi,
I write gaming news and reviews for a site that averages 250k unique visitors per month. Moving into getting involved with the actual writing of a game is pretty much the stuff dreams are made of for me, so you can bet that I'm pretty damn excited about this opportunity.
I've put in a speculative bid based on my hourly rate and an estimate of the time spent on this project. To get a more accurate price, we'd definitely have to discuss what you're looking for. For the moment, though, I imagine you're after something like this:
1. I download and spend some time with the Sky Hammer demo.
2. I then pitch ideas to you through chat or email, and we start to both get a feel for what's going to work.
3. A first draft is submitted to you, which we then deconstruct and discuss together to look for what works, what can be omitted.
4. If necessary, alterations to the game itself are made.
5. I rewrite and edit as necessary and come back to you with a final draft to implement.
Since you've indicated that Sky Hammer is a puzzler in part, I'd say straightaway that unlocking information by finding hidden items or completing extra objectives would be a functional, if well-worn way to establishing some of the finer details of the world your game is set in.
Anyhow, if you're interested I'd really love to hear from you so we can discuss more details! I tend to find myself writing about and playing smaller indie efforts as it is, so I think we could do some really great work together. :)