Yarn Preferences?

Taking a break from my regular (ha, regular?) posting topics to ask a question.

Some background info first:

I signed up for a couple craft shows. Ever since I was young I wanted to participate in them. (Only then, I probably wanted to color or paint pictures. Or sell mud pies.) So I am finally doing it. They aren't for a year so that gives me plenty of time to build up a stock of items. I am wanting to focus on baby\child items and here enters my question.

I want to offer quality items but also do not want to break the bank when it comes to yarn selection.

So, to those of you who are full of knowledge regarding baby yarns, which brands do you suggest? Which are a good quality for the price? Also, which offer the best yardage for the price? I am definitely wanting to use yarn that is machine washable. If you had to chose your personal top two, which would they be?

And to the readers who do not knit\crochet, if you were to purchase a hand-crafted item of the yarn variety, would you be picky as to the materials used? Do you prefer to buy something and know that it is made with good yarn or could you care less, as long as it is adorable?

Thanks for reading and helping me get started!!