The Foresight War by A. G. Williams
I purchased it as an ebook as it was far cheaper. Its an excellent read with a good storyline. The pretext is a historian being sent back in time to 1934, then realising that he can change the course of WWII. Theres lots of detail about the alternative weapons introduced but a compelling storyline holding everything together as well. There are little asides as well giving a human factor, e.g. an Avro Manchester on a mission over Germany. The ending is unexpected but on reflection probably the best ending the book could have.
There have been a few spinoffs on Tony William's forum as well;
ForeSight America by Paul Adkins
This one is free but isn't quite the same as the above. It was done as part of National Novel Writing Month. In this the throwback is a black American history professor. It focusses mainly around him but interacts with characters in TFW as well. It emerges that there are many throwbacks, American, Japanese, Italian, German, British and Russian. This makes things extremely interesting, but it focusses mainly on the US side. The story doesn't really end, it just stops. This is acknowledged by the author at the end along with a few other points. Its still a good read though.
Foresight Italy by Luciano M. Trentadue
This one is an actual novel in progress being written in Italian for Italian consumption. It uses the same pretext of a throwback to 1934. It has developed into two separate stories, one that deals with the Spanish Civil War, and one that will deal with WWII. The throwback is an engineer rather than a historian which leads to interesting developments but his knowledge of events is poorer which means he can't help with strategic decisions as much in the other scenarios. It has a different focus than the other two but isn't likely to be around soon to read. A few points of what I do know; Libyan oil, a different Civil war with considerably advanced Italian forces leading to a different postwar split, Italy building the bomb in an effort to stop post-WWII communism, gas turbine powered destroyers, jet aircraft, antagonism with Germany....The hard part for Luciano in writing is trying not to get too advanced, only in some applications boosting technology to Korean War levels etc. He seems to have been relatively successful.