[plt-scheme] environment questions

Hi All,

Sorry if this is a RTFM, but I can't find it.  (I am also new to both scheme and 
plt, though a linux hacker of 3 years...):

What library procedures are available for inspecting and modifying environments? 
  I would like to do two things primarily:  modify the symbol table to create a 
memoize function a la PAIP; and dump the environment to text, restoring later 
with an eval.

If someone could just point me to some docs on this, that would be great.  Also, 
if there is a step-by-step cookbook for setting up a webserver, that would be 
pretty helpful too.

THanks!
W