Motorola, the builder of the 68HC11, gives lot's of information about the various chip sets. Including user manuals.
See also the discussion group about the 68HC11.
Spasov's home page
This man wrote a book about the 68HC11. Maybe you can find some useful things next to his student info.
Freeware files for Motorola
The Motorola freeware site.
Roger's Embedded Microcontrollers Home
Roger Schaefer has a page with a lot of useful links for those interested in Motorola MC68HC05, MC68HC11 and MC68HC12 Microcontrollers.