I need info on cheap flights from Galapagos Islands to London, one
way. (I'll be arriving their by boat.) Need to know if I can purchase
from the UK and/or if flights are readily available for me to purchase
on arrival. Rough time of travel is February 2005.

If you google Galapagos+air flights you will get some answers.  There
are only two airlines that fly there(due to Ecuador Govt restrictions)
and they will take you to the Ecuador.

You can reserve from this to websites from Gapapagos to Guayaquil (its
more cheapest than quito).
the cheapest ticket are from aerogal
http://www.aerogal.com.ec

or you have these other company (yo can reserve online the ticket)
http://www.tame.com.ec/english/home/default.asp

and you can buy the ticket from guayaquil to London over the internet
from the website:
http://www.expedia.com
or
http://www.cheaptickets.com

If you want to make sure to get the best prices to the Galapagos you
are better off purchasing the ticket in Quito or Guayaquil.  Any
travel agency in Quito or Guayaquil will sell you a ticket for a
standard price.

If you purchase a ticket directly from or to the UK the price will be insane.