magazine files/music storage

[RunAwayHome]

I'm trying to find a way to make my piles of sheet music, music books, etc look a bit tidier, but still be easily accessible.

I have two large wooden shelves. The bottom one is about A4 size deep, and the one above it is just a bit further away than the height of an A4 folder, so I thought I should be able to get something to fit on it that would store the music nicely - was hoping for some kind of wooden dividers or the like, or a set of shelves that could be turned sideways to fit in, or a series of magazine files or something.

The problem is that the shelves are only JUST deep enough (22cm) for A4 things to fit. And all the magazine files that I've seen are deeper than that - only a few centimetres, but it's enough to stick out and make it look kind of ugly. Especially as I'm hoping to find some quite cheap solution - cardboard magazine files would be fine as long as they were flush with the edge of the shelf, if you see what I mean, because you'd hardly notice the cardboard - they'd just be dividers. But once they start to stick out, it's really obvious that they're cheap things. Anyone know of any kind of magazine file, shelf divider, or anything else that I could get that would fit shallower shelves?

They need to be open fronted so that I can slide music in and out of them without having to lift a box off a shelf. I know there are some magazine files like this. Just too deep.

Some kind of expandable vertical shelf dividers? Anything like that exist, and not cost a fortune? At least magazine files you can get for only a couple of quid each. I'm trying to keep the room looking like a sitting room and not like an office, but at the same time I have to be practical and not spend much money.

thanks!