I'm going to oversimply my example for the sake of making my point, so
please don't ask "why bother doing that?"

Sheet1 has a list of product ID (SKU) values.    Sheet2 has a list of *some*
of those values, plus another cell that represents the cost of that item.
How can I put the cost value from Sheet2 next to the ID value in Sheet1,
where Sheet2 has the cost.

Example of Sheet1:

ID                COST
123              {the formula I want will pull the $75 value from Sheet2
data}
124              {the formula I want wont find answer in Sheet2 data}
125              {the formula I want will pull the $20 value from Sheet2
data}
126              {the formula I want wont find answer in Sheet2 data}

Example of Sheet2:

ID                NAME                COST
123              Golf Club             $75
125              Book                    $20

So what formula can I put in Sheet1 to pull the cost data WHERE IT FINDS A
MATCH in Sheet2?   Thanks.