I'm trying to remember the name of either the series or the specific book I'm thinking of. One of the books in the series had some sort of ghost truck in it. Another I remember a little better, about a girl who interacts with an artificial brain who eventually reaks havoc and has to be stopped. The twist at the end is that she finds the plans for another fake brain with an anagram that makes up her name.

Any clue which series of (kids) horror books these are from?