County routing with .htaccess

Hello

I have the following questions:

We have two sites www.ontecmedia.de for german users and www.ontecmedia.com for international users and we want to install a routing that lead automatically on the german site, if german was detected as the browser language and in all other cases, on the english site.
This routing should be done automatically and without the use of manually clickable flags, icons or the like.

I would like to realize this on the htaccess file ... what is the best way to do this? Please note that I have to do this in a live environment and i do not have much experience with htaccess modifing.

kind regards

ShadowLupina

Don't know about .htaccess but http://www.jameslittle.me.uk/detect-visitors-country-with-php-mysql/

Here is an example using the Babel plugin. It has an example of how you can write the htaccess code and a gateway plugin in MODX to correspond with it.
http://www.multilingual-modx.com/blog/2011/seo-friendly-multilingual-websites-with-modx-and-babel.html