Do you have a stroller with a basinett?
Is there a restaurant within walking distance?
Put the baby in the carriage and walk to the restaurant and bring the bassinett inside and let the baby sleep

I one brought mine in with a 'moses basket'. 6 weeks old. Slept right thru in the basket on the seat

I'm honestly curious why you wouldn't just hold your baby... We have been eating in restaurants together since our child was approximately 3 weeks old; he's perfectly happy perched on one of our shoulders watching other diners or sitting in a lap playing with a soft toy. Just go during times your child would be least fussy (e.g., right after a nap) and relax...it's easy. And, if your baby needs soothing, he's right there -- no wrangling him out of some contraption.

We bring our stroller into restaurants all the time, large and small, local and chain. Only one restaurant had us fold it up and put it in a coat room. Usually they put us at a big table and take away any extra chairs.

do you know in advance that the restaurants on your vacation route veto strollers? And for the record, my DH and I are not entitled, pushy people in the least. We just walk in with it and the staff always finds us a spot without any comment. I guess we are blissfully ignorant that strollers are frowned upon?

Worked for us:
http://www.amazon.com/Chicco-Caddy-Hook-Chair-Red/dp/B000A7V1EM/ref=sr_1_17?s=baby-products&ie=UTF8&qid=1324079725&sr=1-17

otherwise alternate holding her

Plan vacations that work with your new life as parents. Eating every meal in a restaurant is not a family friendly plan and you will just end up disappointed. The options everyone posted are great for occasional meals out, though.

How come you don't want to hold her in your lap and feed her? Wouldn't that be the easiest? Then you don't have to worry about bringing anything!