I put this together in response to a question on the Solstice Forum, but thought I'd share it here.
I think it is complete, but feel free to post corrections and/or additions.
I don't have any reason to believe differently. The painted aluminum, polished aluminum, chromed aluminum are all Chinese. Unless someone has definitive information that these wheels are made somewhere other than China, I will assume the MB093 10 spoke and the MB222 Snowflake are also from China.
The Q9Y split spoke from the Solstice Street Edition are also Chinese, as are the Q9Y split spoke from the Sky Special Editions.

Left Solstice Q9Y, Right Sky Q9Y

EDIT: Added part numbers:
The following are part numbers I have found via internet search, I believe they are correct, there may be other GM part numbers applicable to each wheel.
If you are ordering these wheels, please verify that the vendor actually has the wheels available. Most GM sites are listing these wheels as "NO LONGER AVAILABLE"
Solstice:
N87 Painted - 09597296
QF8 Polished - 09597297
PD5 Chromed - 09597298
Q9Y SplitSpoke - 09596706
Sky:
N87 Painted - 09597292
QF8 Polished - 09597293
PD5 Chromed - 09597294
Q9Y SplitSpoke - 19181777 and/or 9596703
Solstice and Sky:
MB093 10 spoke - 17802094
MB222 Snowflake - 17801223