I concur with Corsair. You're not going to find Babylon5 like modules, you've got to write your own material.
I've been running a B5 emulation in D&D for over a year now. So I've got some theories and actual practice in.
My approach was as follows:
make a list of the B5 races and factions, then map those to D&D equivalents.
In my case, the most direct were dwarves=narn, gnomes=Centauri, elves=Minbari. Human Mages=PsiCorp. Shadows and Vorlons = surprise races yet to be named...
The general premises of B5 were:
it takes a while to get somewhere
every body has secrets
every major human character in the show has some relationship to EarthForce
humans are newest to the scene (lowest tech, least knowledge of other races)
I translated all of that to:
PCs can only be humans (thus constraining them to one side of the plot line and not revealing too much)
PCs must all be in the Navy or working for the Navy.
most of the world is ocean, so this is a seafaring game (akin to space travel)
Wizards have only existed for about 200 years, thus lower magic
Gnomes gave humans secret of sending crystals, which allow long distance communication (and enables longer distance colonization control).
I also wanted to start where the series does, with experienced PCs. To do that, I wound the clock backwards and began the game before the Earth-Minbari ware equivalent. Thus the PCs experienced it, and then I jumped time forward in two year increments, so they'd get a feel for time passing. I'm just about ready to start where the series begins, after a year and a half of running the campaign.
I've been able to recreate the Battle of the Line and other key scenes from that time period.
Things to remember, it's very easy to railroad when you follow a TV show time line. You've got to watch out for that. I've done fairly well in predicting reactions (limiting the allowed PCs helps with that).
On the other hand, you don't have to reproduce the show in exact detail. Sheridan/Sinclair is the same character. The same for Talia/Lyta. JMS adjusted for casting changes. You can too.
The key for reproducing the show seems to be:
a central location the PCs are in charge of
various factions (whom the PCs simply can't kill), working against each other
external threats like pirate raiders
a "chosen one" hero to sacrifice themselves
interesting backstory revelations that affect the game for each PC
the player info site I built is below, if you want to see what I got so far
http://ken.scbwic.com
