Sears has this jack (1.5 ton) on sale for $89:
http://s7.sears.com/is/image/Sears/00950240000
And this one (2 ton) on sale for $150 (if you're a Craftsman Club member):
http://s7.sears.com/is/image/Sears/00950239000
My other vehicles are easy to get under, had to come up with some new tricks to get under the Miatas...