calling XML data

this is my first real XML project with Flash.
i am trying to get the node value into a variable in flash MX.
i am imagining that you could call that data with some simple code like: var = file.parent.node , or something like that.
i have a file that loads the XML into flash, but it makes all of the data into an array, so i need to know the position in the aray in order to find that variable. (if it is first , i set the array position to 0)
the database that i am workign with now is going to have around 6000 items at any given point, and will change constantly.
it is impossible to know where in the array the data i want will be.
i want to define the data in this way:
parent >>> item number (000001) >>> price.

i will know exactly what the item number is for each variable that i want to set.

can you tell me how to tell my variable to find what i am looking for?

thank you,
TR1