< 2 inch/ < 5.1 cm amphibians?

[Jheuloh]

TL;DR version of below parargaph(s):

What species of terrestrial amphibians can be regularly found CB/CB&B and don't grow over two inches or so in size?

Paragraph(s) below:

Having recently begun to fiddle with the concept of raising 'bio-active' terrariums with various things collected from a good friend's backyard, I've begun my first dive into the venture with a 23.3 x 18.7 x 12.3 in rubbermaid bin, currently filled with ferns, clovers, lichens, fallen leaves, sticks, logs, etc. Basically a little bit of everything that would (and did) occur in a backyard. With that said, it's extremely humid, and I figured a terrestrial amphibian would be a nice 'final touch' to my Backyard in a Box. Anyways; with that said, the rubbermaid bin is 23.3 (length) x 18.7 (depth) x 12.3 (width). Being extremely cluttered, I couldn't imagine an animal larger than 1.5-2 inches in length inhabiting said terrarium. I'm not well versed in what species of amphibians exist in the pet trade, (compared to what I know about which reptiles are located where in the pet trade, that is) and the only species I can immediately think of are the various poison dart frogs and the red eye tree frog.

I know those are only two types (well, to be more specific, that's just one species and a family) of amphibians, and there's certainly more out there. I don't really know where to begin my search, so, I ask the better versed in amphibians; where would I want to look for a small & terrestrial amphibian?

Edit: When I say "Red Eye Tree Frog" I'm referring specifically to Agalychnis callidryas.