My astrobiology book is quite officially out now ! 

It is aimed at both college students and general readers interested in the role of Life in the Universe.  That is, what did it take for life to arise, how did it evolve, how likely is it that similar things may have happened elsewhere in the Universe ? 

You can order the paperback from Amazon.com  here:

http://www.amazon.com/gp/product/0801883679/

for further details and links to the hardback and to the other amazon stores (uk, de, fr) visit my page at:

http://www.geocities.com/michaelgrr/edge.html

enjoy, michael