I need to show a text label within a section column on page layout.
I've created a separate section and new VF page.
I need the text label to appear both on create and edit of the record.
Visualforce pages do not show up on create/edit pages. You would need to create an entire create/edit Visualforce page and override the new/edit buttons. This would either mean hard-coding field names, or writing quite a bit of code to support record types, dependent picklists, etc.