Laird would rhyme with "cared", having the same sound as the word "air" in the middle.
Llew is almost nonexistent in the USA; probably most Americans upon seeing it would assume it is pronounced the same as
Lew, though that wouldn't be the original Welsh way to say it.
Yair is problematical. Most "Anglo" Americans upon looking at it would rhyme it with "air" and put the y- sound of the word "yes" in front. However, this name is I believe often used by Hispanic Americans, who would be more likely to pronounce it like the English word "gyre"-- the "j" sound of "just" followed by "ire", rhyming with "hire" or "fire".