[Zope] How to explore the BTree Folder

Can anyone point me in the right direction to explore the BTree Folder as I'm currently using the Default Folder on my live Zope/Plone Site and would like to change my Folders to BTreeFolders to handle more than a few thousabd objects obviously on my development server (Test & re-Test )prior to deploying onto my Web Apache/Zope Server that is live and kicking. I have read the Zope Bible but I can't not find a reference to BTree Folders . Also DirectoryStorage and DBtab would advantageous - just the url or procedure. Thanks 4 yr attention .