I'm searching for any information on interactive kiosks or tabletop
units where a restaurant patron would have an Internet terminal at
her/his table. It would be supported by advertising. The match I'd
like to get is:  what companies are providing a unit that is attached
to your booth or table, where you sit down and surf while you're
waiting for your food. The unit is subsidized by ads.

Have a look at http://www.kiosks.org/
This is the industry association for suppliers of all types of kiosk,
and has links to suppliers of hardware and services.
There is also an online RFP service where you can submnit a request
for proposal to 139 companies.

Hope that helps.

If you want a company that will supply an interactive software and the
hardware try Campus Vision, they are UK based software developers with
loads of screen experience. www.campus-vision.com Dont be fooled by
the student based web page, that is just the major project they run.
I have worked with them before and they are very good.....but not cheap.

However I can tell you from first hand experiance in restaraunts and
cafes that advertising wont pay for it and advertisers wont pay to go
on it. The audience demographic is too low in numbers, too diverse and
tends to be in the low spend sector. When you move to the upmarket
restauraunts they wont touch it, as for them the food and the service
is what its about.

Good luck if you are gonna try it, but I know of 4 other companies
other than ourselves that have done the reserach and dropped that idea
like a hot brick.