For small bank notes, Dansco has a great album for raw notes -- 7001.
See this CCF Topic for pics and discussion. It comes with 9 pages but you can stuff it with at least double that. I very much enjoy this format and have several albums. There are also numerous other options for displaying notes in binders. You can store graded notes in a box. I have a couple of Lighthouse albums with VARIO pages for my world notes. Also top-notch stuff.
For "from circulation" coins, I like to use the Whitman Classic albums (not folders, but those are fine too!). Relatively cheap and good quality, and you can get many of them for 40% off at Hobby Lobby with their e-coupon. The reason I prefer albums over folders is you can see both sides of the coin. Of course Dansco is another solid option. CAPS is a good option, but very large and expensive.
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I can't find much selection.
You're limited to a few major options: e.g., Dansco, Whitman Classic, CAPS, Liberty, Lighthouse. There are numerous coin supply sites out there. Just do a bit of Googling.
Or, buy a binder and some pages that accept flips and make your own.
Personally, I use all of the above, but enjoy the commercial offerings for the look on my shelf.