If you pump Barrowmaze into google images you'll see all kinds of pictures and illustrations.
We also have session summaries (start around number 16) at our campaign wiki:
Welcome to Red Box Niagara - Red Box NiagaraFun story: When I was at NTRPGcon I had a chance to meet Erol Otus. He said that he thought the monster section of Barrowmaze was "just perfect." Needless to say, I didn't need a plane - I just floated home!