Glest WikiFirst of all, the Glest Wiki is the first result when googling "glest mods" and many other varieties of Glest, so is the best place to have your mod hosted, as it will outperform this forum board, modDB, and the Glest Guide. It is also more customizable than the board, allowing some HTML codes and boasting a lighter color scheme.
The Wiki uses the exact same syntax as Wikipedia, and pretty much all wikipedia code will work on the Wiki, plus more, such as image galleries and other things that Wikia added on. I would recommend
http://help.wikia.com/ for learning how to edit, as well
http://en.wikipedia.org/wiki/Help:Contents. The wiki also has a WYSIWYG editor (What you see is what you get - similar to how a word processor works), though I would advise using the code view if you can, especially with tables, as the WYSIWYG editor tends to add unnecessary code sometimes and has limitations with templates and the finer attributes of images.
At any rate, regardless of how you choose to edit, I advise taking a look at the
UNATF faction pages, as it is the only completely documented faction so far (faction, resources, units, upgrades, and attack/armor types), though
Magitech and
Constellus are partially completed as well. It would be a good idea to try and maintain at least a little bit of consistency. Your page has already been started, and as the faction and techtree have the same name, the "Imperial" page is a disambiguation page. If basing off the Military page, don't worry about the navbox at the very bottom. That's a rather complex bit of coding that has the potential to go terribly wrong, and I will add them myself to every completed mod documentation.
How easily editing the wiki will go will depend on how much you've used other wikis and wikipedia. In all honesty, wikipedia is a huge role model for the wiki, though we are not wikipedia, and do not require references or fully encyclopedic writing, though a neutral point of view is a must.
Glest:Policies may also be of use, as well as
Glest:Style guide.
I sense Omega will come here soon and tell you to make pages for each individual unit, which I suggest you do too.
Technically, you said it first, so I don't have to, though I will anyway. Of course, focus on fleshing out the faction and techtree pages first, as they are the most important.
Have fun.