We have a member here who recently hired YourMechanic.com to inspect a used car that they couldn't inspect themselves and appeared to be satisfied w/the service.
As for parts, as long as we have enthusiasts sites (skyroadster.com & kappaperformance.com) the members should be able to help you find parts in the future. Plus salvage yards continue to part out Kappa's and sell parts online. Also remember that while the Sol and Sky have different body panels most of stuff under them are identical.
While you say you want to stick w/dealerships I wouldn't discount looking at private sales since you can sometimes get more information about a car from an owner. I have two different threads I update on a daily basis. The first is a low priced thread (around $5K) and the second is a low mileage thread (under 20K miles). Most ads are from Craigslist because I feel they offer the most up to date format.
Low-Mileage Solstices For Sale
For example here the latest entries:
2008, 2.4, Manual, Cool (Silver), 9,002 Miles, $9,600, Salisbury, NC Looks to be a good buy
2006, Auto, Aggressive (Red), 18,000 Miles, $12,500, North Mississippi
2008, GXP, Auto, Brazen (Orange), 13,000 Miles, $15,700, Pewaukee, WI
2008 Pontiac Solstice GXP 13,000 miles (pics)
2007, GXP, Manual, 22,500 Miles, $16,500, Loveland, CO
FWIW, two out of three Sols have auto's, making manuals rarer, and I'm going to assume you know that Pontiac also offered 1266 Targa coupes in
Also, check out this place, they purchased OEM parts from GM when they closed the Kappa factory: http://www.factoryoemparts.com/ponti...ce-saturn-sky/