Create a child SPListItem under an SPListItem

I have an SPListitem in my list.

The requirement is to have the ability to create a child or a component under that SPListItem.

For example:

SPListItem = Honda

and my user wants to create a child item under that honda, and will enter the details (mode, year, engine etc)

How will I do this?

what approach should I do on how the users can add a child under the parent SPListItem? (web part, custom ecb, ribbon etc)

Thanks!

----------------------- Sharepoint Newbie