Lakoff and Johnson are the authors of an outstanding and accessible introduction to ConceptualMetaphor titled MetaphorsWeLiveBy. It belongs on everyone's BookList.
- GeorgeLakoff is at CalBerkeley as is the ConceptualMetaphor home page containing the Library Of Metaphors: http://cogsci.berkeley.edu/.
- MarkJohnson is at the University of Oregon as is the Center for the Cognitive Science of Metaphor Online: http://philosophy.uoregon.edu/metaphor/metaphor.htm.
I'd recommend WomenFireAndDangerousThings by Lakoff instead of MetaphorsWeLiveBy. It develops the same argument much further.