There's a few included with the game.  Other than that, just heard about a couple folks looking into it. 

I would say using Ecomental map maker is your best bet. I have actually been getting repeating crashes from my custom maps. They also use custom lairs and such that would probably not go over too well. Hopefully someone releases a stamp pack soon. I would do one, but my time is used elsewhere.

Overall, I'm pretty disappointed with the modding tools in their current state. I hope the situtation improves. If it doesn't then the FE modding future doesn't look so good.

you do realize that most companys that allow modding don't even release tools for its games, they leave it up to the community to come up with their own for the most part.  So i really don't see how the state of the tools will affect the future of modding with FE, in fact i personally see a bright future.

A few pages of good documentation covering the critical stuff would be a good start and not involving a huge effort on their part.

I realize this has been a low priority for them and I understand why. I'm not upset by it. My observation from being involved with many modding communities for other games is that if you build tools and document them to at least some degree, it opens up the modding to a much wider group of folks. There are always the hardcore, dedicated modders with some coding experience and the time to spend that it takes to learn things from scratch. But, there are not that many folks like that, trust me. Tools are good but if they are not very intuitive (they aren't) or they don't have decent documentation or tutorials for a new and enthusiatic modding base, then most new modders will finally give up in frustration. That greatly limits the future of modding for this game and I don't want that to happen. I've seen it over and over and over. Right now, HoMM6 is a classic example of this. I'm already seeing some signs of this for FE on other forums I frequent and I hate to see it. Right now there is a high barrior to modding FE. 

+1 for the moddings wiki

Are there maps bigger then large from game random generator?

I want huge maps, no, I want biggest mofo maps possible.

The usual large sounds silly...

as long as ecomental has no downside using the beta .99 files as they are different to 1.0 i would say go with ecomental myself as the author of that mod has much larger plans to fix the map generators by doing new and better stamps for it.  This is coming from the author of Fe-enhanced, i know when to admit i don't have the talent to do what some of these modders do, with that said both mods add 2 new sizes, one being 10x8 and another being 12x8 which is the max without throwing a warning ingame, the default large map is only 7x6 by contrast.

is it possible to have bigger maps then large and with more AIs and lasting more then 1000 turns?

The 1000 turn limit is only for high score calculation, your game continues afterwards if you want to.