Custom module tutorial

Where can I find a step by step tutorial to develop a custom module. It must have db, administration, ajax, image...
I just have read the documentation but... I dont understand how to build a real module like e-commerce.

Is my first time in this CMS. Sorry for my english.
Thanks.

GIO05

sottwell has a module tutorial on her site that is pretty good:

http://www.sottwell.com/database-module.html

You can log into the site and see it in action as well.

Thank you for the link...
This is very basic tutorial...
I’m looking form a tutorial to develop modules who use a proper table...
In my idea this module shud have a install file to install it in many site, many db table (olso this shud be created in installation...)...
I hope you can undestand whot I mean...

The second and third articles in that series go into those topics. The third file download contains everything for a working database access module. All you need to do is adjust for the fields you need.

I guess it’s also useful to have the API functions handy when working on a custom module:
http://wiki.modxcms.com/index.php/Category:API_Function
http://wiki.modxcms.com/index.php/API:DocumentParser