Steering went into lockup.
 

Just had to fork out approx $750 for a tow and replacement of a theft lock actuator on my 2000 conv. Understand this is a problem with the C5 series because the dealer told me there had been an earlier recall where some other part had been replaced. He said my current problem didn't qualify for a free fix. Obviously at 36K miles I wouldn't expect a run of the mill issue to be fixed free on a car 13 years old.

Since this earlier recall didn't solve the problem, it makes me a little uneasy about keeping my car! If this is a serious problem across all C5 vettes it looks like grounds for some type of class action suit vs GM. How widespread is this problem?

Extremely widespread. In fact, I wouldn't be surprised if 95% of all C5s have had that problem. Back when it happened to me, the dealership service manager told me that only automatic tranny C5s had a blocking plate installed to permanently disable the column lock feature. Since I have an MN6 tranny, they simply replaced the actuator.
So when I arrived at home, I installed a CL bypass. That was many years ago and I have never had a problem, since. You should do the same. I believe I bought mine from West Coast Corvettes but other vendors have the kit as well. Cost is about $50.

Yeah, it's the most common problem with C5 Corvettes. I didn't go with the device which requires removing all of the column stuff, rather this easy to install device from these guys:
http://complianceparts.com/lmc5unlocker.html

My car had the GM service done, however I installed this one anyway. Good luck..

thanks for the info

Get your money back! That should have been a recall!!! I have a 04 conv. manual trans. They told me I was crazy about the lock out. Had it at the dealership three times and they always said nothing is wrong. When I was backing out of the parking lot the steering wheel locked! I left it sitting there, got the service manager out to the car and what do you know...they said it is the locking ring broke loose and they didn't see it the last three times. Call the district manager now!!!

From what I understand, there was a recall, however it's no longer considered as such because of the age of the vechicle. It can't hurt though to call the DM as mentioned above, just don't get your hopes up too high..

Thanks for the additional info. My dealer attempted to get Chevrolet to cover it but it was past the time for warranty or recall "freebies".