I also highly recommend "Semantics with Applications" by Nielson and Nielson. I read it this January and it is an excellent book. It is very approachable for someone with only the lightest background in formal methods. If you are looking for a good introduction to the field I would start there. I am definitely going to look into the OPs book it looks awesome.
after reading the author page it looks like the OPs book has not been updated so keep in mind that it is the state of the field as of the 80s. The work by Nielson and Nielson is fairly recent. I would also suggest "Principles of Program Analysis" for a follow up book.
download http://www.daimi.au.dk/~bra8130/Wiley_book/wiley.html
print http://www.amazon.com/Semantics-Applications-Appetizer-Under...
EDIT:
after reading the author page it looks like the OPs book has not been updated so keep in mind that it is the state of the field as of the 80s. The work by Nielson and Nielson is fairly recent. I would also suggest "Principles of Program Analysis" for a follow up book.
http://www.amazon.com/Principles-Program-Analysis-Flemming-N...