Hey Fran, This one's for you.

Over the course of time,  I've looked for web resources that illustrate
database design principles, so that I can refer to them instead of typing in
the same responses over and over again.

Here are the best two I've found:

http://www.databaseanswers.com/

this one has about 200 data models that you can grab right off the web.  The
models are in the form of an ER diagram (for conceptual models)  or a
relational schematic (for logical models).  In addition,  the owner will
send you, by e-mail, an empty MS Access database derived from the model,  if
you send an appropriate e-mail to him (or to his mailbot, I guess).

These models provide functional examples of minimal level models for a
variety of situations.  You can typically use one of these models as a
starting place for prototyping your way up to a full model.

http://www.utexas.edu/its/windows/database/datamodeling/index.html

This one contains a bare bones introduction to both the ER model (conceptual
data modeling) and the relational model
(logical data modeling).   It's not perfect, as some regulars in
comp.databases.theory have pointed out,  but it's very good.  It lays out
the essentials in a format that's easily followed.

I particularly like the fact that it differentiates clearly between
conceptual data modeling and logical data modeling.  There are many experts
who skip right over conceptual modeling and start out right away with
logical modeling.  I think that's a mistake, when it comes to discussing
information requirements with subject matter experts that may be very naive
about data.  But other professionals report the opposite experience.  Go
figure.

Anyway,  I hope this helps.