Got a email from a very nice lady named Riki, over the weekend, asking about writing tie-ins. I thought I'd reprint my response here, because I get asked this a lot, and it may be of interest to a few others out there, wondering about the process.

Fandemonium will accept un-agented manuscripts. 

As for researching any tie-in, my advice is watch every single episode of Stargate: SG1 and Atlantis several times, looking at each episode from a different character’s perspective.

As for other historical or scientific research, don't kid yourself that a tie-in takes any less work than a regular novel. If anything, it takes more because you have the added burden of fitting in with the existing canon and are not permitted to deviate from it. Nor are you allowed to fundamentally alter the characters or have their journey alter them – i.e. you can’t scar them physically, or mentally either, for that matter, if the experience would fundamentally change their nature. If I could give you one example – you couldn't write a story where Rodney McKay has an epiphany and suddenly turns into a Sensitive New Age Guy. :)

Oh, and the characters can’t swear unless you can prove they’ve done it in the show and can name the episode (hence the reason it pays to watch all 13 seasons of both series and take notes).

Try your local library or the internet for historical and scientific research. Contact universities and ask to speak to someone in the faculty concerned. We researched Roswell for months prior to starting it. Getting the facts right is the burden of the author, so you check, and read, and ask experts and recheck and then be prepared to defend every fact when MGM get a hold of it, if you are lucky enough to get accepted.

Be warned, however, that it is no easy task. Fandemonium get hundreds of submissions each year and accept very few, because, in addition to the above reasons, in many of them, the writing is, well, bad. Tie-ins have to be every bit as polished and well written as other works of fiction and the reason they tend to be written by authors who already have a body of published work behind them is the same reason you’d hire an experienced chef over an inexperienced one, if you had a very successful restaurant with a long history and a good reputation to protect.