On the same subject, if anyone knows of a good tutorial for me to be able to build my own buttons, please get in touch
I am not aware of a tutorial.
But if you have a look in the themes folder/directory in the templates folder/directory then it's not too difficult to figure out the structure and components that comprise of any of the default sets of themes. The XML files (which you can view and edit with any text editor) contain internal comments that explain what's what.
So to create you own theme one approach would be to create a copy of an existing theme and modify it.