dividing up categories to fit menu

This isn't exactly a template question but I need help in figuring out how to tackle dividing up my categories so they fit the template menus.
I have a long list of supplier in alphabetical order on the frontpage. This is good and easy to find the supplier at a quick scan down the list.
Also I have in the top menu regions around the world, asia, europe, etc.,
I want my suppliers to appear under their relevant regions as well in the top menu without distrubing the long list of them on the front page in alphabeical order.
At the moment they are ALL simply under the one parent category SUPPLIERS and that is how I can get them to appear in alphabetical order in my list on the frontpage. I am concerned that if I start didviding them up I will interfer with the look and function of my long aphabetical list. Yet I still need them to appear in their own region under each menu item in the top menu?
Anyone have any suggestions on how I can do this?

Hi,
they are many ready solutions.
If you are using articles you can use filters, for example:
solidsystem.it/joomla-extensions/dropdown-articles.html

but the best ones are for K2 items --> styleware.eu

Remember that you can use module inside menu. We have guide how to do this.

Hi Pawel I followed your advice and went to styleware.eu and asked advice and explained what Im trying to do.
This was their advice -

I'm not sure how this question is related to our products...

I assume that you are using K2 for content management.
The answer is: use K2 items for suppliers and tags for regions

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Yep I am using K2 but I have no idea how to do what he suggests. Where can I learn how to do this?
Thanks Man.

I will try to help,
if you are using Joomla 3.x - you don't have to use K2 to have tags, because Joomla 3.2 (J3.3) have tags system in-build.

But if you need K2 items - they have many useful features which can use.
They have tags system and custom fields - which allows you sort items by those "elements" also add Filter Items module inside menu.
You have to play with this for a while... to check all features

Alright I will start and let you know how I go. Thank you for the help it is much appreciated.

Well its been a confusing but large learning since I posted I have educated myself about tags and written in several K2 and Joomla related forums trying to solve this. What I have found is K2 categories which is what Im trying to work with, can't be tagged. Joomla have caught up with 3.2 which I have and they can be. But that does help with how I was trying to go.
So I now have started adding the K2 categories to each menu individually under new ( sub ) ' menu headings'. It solves my problem. Thanks for your help guys. Great work love the template.