help pls: how to go about implementing a custom database with modx

could someone point me to a tutorial or some info, i’ve been searching last 3 days without much luck.
I want to understand how to implement a custom database within modx, with custom forms administering the custom database from within the manager itself. I’ve heard about xPDO and TVs but cannot find any examples where i can educate myself enough to start implementing.

the custom database will be a dbase of hotels with varying pricing throught the season. I dont have a problem laying all this out in Mysql, however i cannot find ONE online example where i can see something similar implemented within modx. THe alternative would be to custom code the admin section & frontend for the site in PHP/ASP and i have had enough of doing sites that way.

I have come upon this
http://modxcms.com/forums/index.php/topic,23176.0.html
however i want to have normal admin screens with forms which i can play around with for hotel editors, not phpmyedit full raw access to dbase.

I’ve also stumbled across this
http://svn.modxcms.com/docs/display/revolution/Using+Custom+Database+Tables+in+your+3rd+Party+Components
however there is no part 2, and it only shows how to create the custom dbase, not how to get users to add/delete records from it.

I’ve also seen this
http://modxcms.com/forums/index.php/topic,32720.0.html
could it be used for my purpose?

Any info welcome please. I just dont understand how i couldnt find much on this topic, im sure there are tons of developers out there looking at modx and asking themselves the same question - or am i missing something?

I think the last one may work for you. You can also look at the tutorial on sottwell.com for creating a custom module which is great and I believe sets up a custom mini db editor as well. http://www.sottwell.com/create-module.html