The book was about miniaturization of robots. The story follows two friends who, through the use of something quite similar to the Matrix movies’ “neck port”, could port into small (~1″ tall) robots. The story starts with a focus around the main characters backyard, in which, porting into the robots, the friends play around, have fun, slaying insects and such. Also, within the first few pages of the book there is an assassination. Which is the “bad guy” using a tiny robot to kill a man while he is driving, the report says that he simply had a “car accident”, though.
The “miniature” robots is a relatively new discovery in the world of science and the only reason the boys have access to it is because the one (who's house the story happens) is the son of the creator.
Early in the book, a person is being given a tour of the facilities where these robots are created and he is shown an area in which people who control micro-sized robots are building things.
As for title or Author, I have no clue, except that I think that " ______'s Backyard" may have been the title. Time frame for publication would be Pre-2000.