You can try creating a custom theme.
import tkinter as tk
from tkinter import ttk
root = tk.Tk()
mygreen = "#d2ffd2"
myred = "#dd0202"
style = ttk.Style()
style.theme_create( "yummy", parent="alt", settings={
"TNotebook": {"configure": {"tabmargins": [2, 5, 2, 0] } },
"TNotebook.Tab": {
"configure": {"padding": [5, 1], "background": mygreen },
"map": {"background": [("selected", myred)],
"expand": [("selected", [1, 1, 1, 0])] } } } )
style.theme_use("yummy")
note = ttk.Notebook(root)
f1 = ttk.Frame(note, width=300, height=200)
note.add(f1, text="First")
f2 = ttk.Frame(note, width=300, height=200)
note.add(f2, text="Second")
note.pack(expand=1, fill="both", padx=5, pady=5)
tk.Button(root, text="yummy!").pack(fill="x")
root.mainloop()
EDIT
The most detailed ttk documentation is from the tcl/tk world
eg.
http://www.tcl.tk/man/tcl/TkCmd/ttk_notebook.htm
For some useful python-based examples, you can grab the pyttk-samples package
from http://code.google.com/p/python-ttk/