George, they are listed in just about every car type magazine. My wife bought me a set in 2005. Ordered them from some place in Florida but I see them in local places ocassionally.
However, I used them ONE time and after that they took up space under my work bench. I finally sold them to a car club member about a month ago for $80 bucks. To move a vehicle I usually just run the floor jack under it and pull the jack! I'm not saying they are not worth having, I just never really liked them. Oh, they were of the first type you mentioned.
When I do see them I have noticed skates that appear to be the same but depending on where you buy them there can be a fairly big range in price for the same thing.... and shipping ain't cheap if you don't buy them local.
