If they are from a major manufacturer like HP, Dell, etc. then yes. I see no reason not to. Circuit City was just a retailer. If you are worried about the warranty, They are one year standard for Dell, HP, Toshiba, etc. and you can go to their websites and get extended warranties from them directly, no need to get Circuit City’s warranty.
Yes, I know they are managed and run through a third party not effected by their closing, but I’d rather get it through the manufacturer to avoid any possibility of circuit city or their third party warranty company not honoring the extended warranty by not getting it through them in the first place and dealing directly with the manufacturer.