This questions seems to be asking two different questions, so I will give two locations for learning more.

First, one primary location for researching the George HW Bush administration is the George Bush Presidential Library. You can find primary source documents of all different kinds. Quite fascinating to simply search through records of presidential libraries using key word searches. You can also search in numerous other ways. However, the reason for your interest--his passing--has also made accessing the site difficult (impossible?) as going to the research site redirects back to a page about the upcoming funeral at the library.

As far as biographies go, I suggest When the World Seemed New. It is fairly pro-Bush insofar as it suggests that the "inaction" that often characterized his regime was calculated and allowed events to play out in a relatively peaceful fashion (speaking here of the fall of the Soviet Union). This balances against those who either accuse Bush of having failed to act to secure a more peaceful/democratic/better/[insert goal here] world or those who suggest that other geo-political actors, such as Helmut Kohl and Mikhail Gorbachev, did all the real work and Bush was on the sidelines.