diffusion of innovations modeling?

howdy.

first off, i realize that this is almost off-topic for this list.  I'm 
asking here because I think there might be a couple (business-educated) 
folks here who would know the answers.

i'm looking for implementations of algorithms for the modeling of 
diffusion of innovations - often studied by folks in marketing 
departments.  one particular resource i've seen is Vijay Mahajan's "Models 
for Innovation Diffusion", published by Sage press in the 1985/1986 
timeframe.

Has anyone done modeling of this kind in R?  enough to have tips or scraps 
of code that I could leech?  :)

I'm just not familiar enough with modeling to know where to dig in.  I'd 
appreciate any help folks could proffer.

thanks,

--elijah

School of Library and Information Science
Indiana University, Bloomington