I ordered them from The Succulent Perch. You can find her on Facebook or email her at firstname.lastname@example.org for a catalogue and order form. They make a really nice gift and are definitely out of the norm. She takes care to try and include succulents that do well in your area as well as will send detailed care instructions. She also includes a list of what succulents are used in your birdhouse. That was pretty smashing for someone like myself who loves details.
After getting a quick shower with the kitchen sink sprayer, mine perked up quite nice from the travel and is enjoying her spot on the kitchen table. In the spring I'll move her outside, but for now she'll enjoy the light from the back window. I'm looking forward to watching it fill in, and since succulents are good about doing that I shouldn't have to wait long!