themaniac,
In the ASM Handbook, Volume 19 "Fatigue and Fracture", you can find a S-N field for Al 7075-T6 whit very sharp notch Kt>12 (chapter "Selecting Aluminium Alloys to Resist Failure by Fracture Mechanics", p.786 '96 Ed.) is a small graph, but is the only reference i know.
A bigune reference in fracture mechanics and fatige is ASM Handbok Volume 19
the oficial gude in damage tolerance in aircraft structures is the Advisory Circular 25.571-1C. You can find it at WWW.faa.gov