Is there anything similar to motorbike roadbook holders for bicycles? Does anybody know if there may be in commerce anything similar to the roadbook holders they use on offroad motorbikes, but for use on bicycles?  

I know there are some electronic versions in commerce that include a GPS system, but I was looking for a cheaper solution (possibly smaller than the one below).

Here's a sample: 

An installed roadbook:
Personally I just use the map case on a handlebar bag (needs to be oriented properly to work), but here's a clever DIY solution by Raymond Parker:



Basically it's a piece of wire bent to prop the cue sheet at the right angle.  Put your sheet in a waterproof case or ziplock and a couple of binder clips hold it in place.  A shock cord keeps the whole assembly in place.  Full instructions here:  http://veloweb.ca/garagepages/sheetholder.html