Only just joined this forum and this is a really old thread but..
I remember Midland Ed well and have fond memories of my time there as a Saturday and holiday time worker between 1972 to 75/6. I used to work mainly with Cath and Mabel on the counter near the cashier's office selling brief cases, slide rules, drawing pens, Letraset, and all sorts of arty/technical stuff. In fact, that whole floor was an Aladin's cave of materials for artists and crafting with resin, lino cuts, basket work etc. A real loss when it shut down.
As already mentioned, the top floor was Arts and Crafts, 1st floor was books, maps, and records, ground floor was stationery, and basement was toys including educational "toys" like chemistry sets etc.
I was on the top floor and Bill Ford managed that department while Mr Gough was the General Manager. I think Mr Laing managed the book dept.
Although people did have tiffs occasionally and there were some real characters, everyone was friendly and it was like a big family. I was sad to leave when I went to Uni (particularly because I'd just met a girl I was very interested in who was also leaving to take an engineering degree but bad timing, confusion, and inexperience with girls let me down there but that's another story !).
Oasis next door was another Aladin's cave. I remember the smell of joss sticks when you went in, and the massive variety of shops ranging from posters to clothing to lamps and homeware - all sorts of stuff. Next door to that was Lasky's hi fi shop if I remember correctly - got my first amp and deck second hand off the manager there.
Up the road, over the island was Virgin Records which, I assume, was the original shop, again with the smell of joss sticks as you went in and people lounging in their flares and Eastern patterned tee shirts on the seats down the middle of the shop listening to albums before deciding to buy.
I wouldn't have missed working at Midland Ed. It introduced me to loads of nice people and gave me some life experience I wouldn't otherwise have had until later. It was a great shame when it was closed down.