It does not really matter whether you decide to do your stationary shopping online or off.
After all, what you can buy at a stationary store nowadays is pretty similar at both online retailers and those that have a primarily offline presence.
Paper and notebooks -- if you are looking for paper or notebooks, you will find any type you need at a typical stationary store on the Internet or off it.
Start with printing paper, then move onto letterhead, paper for invitations, posters or photographs. You will find all of these types and more at a typical stationary store.
If notebooks are the things you need, expect to find these in a huge number of styles, sizes and colors.
Tape -- A typical stationary store will stock a huge variety of tape.
If you are looking for packing tape, you will find it. If you need pretty tape to wrap presents with, or washi tape for handicrafts, you will find that too. In fact, every type of tape imaginable is usually stocked at most stationary stores.
Pens and pencils -- No matter what kind of pens and pencils you need, you will find these at all stationary stores.
You can start with the typical ballpoint pens for writing with, and then move onto calligraphy pens, drawing pens or pencils and those used for making posters.
You will find marker pens and pretty pens from Japan that are decorated with anime characters.
Gift wrap and tags -- If you are looking for paper to use to wrap gifts and the tags used to address it, almost every stationary store will sell these as well.
You may check stationery store for more.