I found these really pretty A5 notebooks at Akademihandeln (a Swedish book and stationery chain) today. They were 50% off so three were €3 or so. My students will be very happy (I give them each a notebook for their lesson notes).
The books have white lined paper and an elastic closure. My absolute favourite is the pink one with the bunny on it. I like notebooks with elastic closures as you can carry them with you and keep the pages flat and together, without things getting caught between the pages in your bag. You can also use notebooks with elastic closures in a TN cover – either close them as usual with the elastic, or use the elastic as a bookmark (which is what I do).
I also found this one at Rituals, a spa shop. It has gilt edged crisp cream paper, a place to keep papers, inspirational quotes, a silk bookmark, a pencil, a pen loop and a round elastic closure. What I really liked about it is that it has plain and lined paper – plain on the left side and lined on the right side. The paper is really nice too.