Small monitor- made in the states

I would go for a small Dynaudio.

Check out Fritz speakers. Most definitely a person, although I think he likes Chinese food, if that matters.

Check out Aether Audio (formerly SP Technology)

BTW, I didn't think of him because you said "on a shelf" which wouldn't necessarily consider to be optimal so this may be moot, but then you're talking about a sub. You don't mention a budget either. If you really want to kick some very serious high-end butt with a monitor/sat system made in the USA, definitely do not miss Duke Lejune's line of Audiokineses speakers. His Planetarium system is amazing! I would definitely put it on my short list if Duke tells you it can work in a bookshelf. Not exactly small, but let me tell you, that system is taking names! Aside from the Planetarium system, I've only ever heard his much larger speaker, which is also VERY impressive but larger than you'll want. Highly recommended with no reservations.

Thanks Jax2, but at this point none of my speakers are suitable for Wombat3's application (maximum height 12").

If Audio Concepts (ACI) speakers are still available, they are excellent designs. What you can't see from eyeballing them is that designer Mike Dzurko makes (in my opinion) the correct tradeoffs in the crossover region, and the result is very natural sound.

I heard Fritz Speakers at the Rocky Mountain Audio Fest a few months ago and was quite impressed with them. Again, the designer is doing something very right in the crossover region.