I actually bought our set on Amazon.com, because that was the least expensive option. They are also available at Barnes&Noble.
They are total immersion, so no English translation (which is why Chick misunderstood that they were showing FEET not BABIES). The creators of Little Pim do recommend parental involvement to make it more interactive, which greatly improves the effectiveness.
Chick likes them. Now that she's more familiar with them she is repeating things back, so at least it's good for pronunciation. I don't know how much she gets from them--I'm afraid I haven't been very involved. Someday soon now [sigh] I'd like to start watching a 5 minute segment with her each day & then using those specific words during the day...how lame am I that a 5 minute learning activity sounds like too much work?!!