Stuck on the following clues. Any help appreciated please.
11A/1D: Text book approach to information Technology... as how to complete a crossword D?/ I?/ D?/ ???/ N?M?E?? (2-2-2-3-7)
8A: It's put on a horse about whose head is lost ???E (4)
4D: Just peerless ?N?Y (4)
Thanks in advance.