Moving Data From One Workbook To Another

I have two workbooks and wish to extract data from the first workbook (second tab), and insert certain cell data into a specific cell in the second workbook (first tab).

The first workbook has this info:
SN
SN
Sort
P/N
Removal
Customer 1
Customer 2
Program
Rec Month

ABCD1234
D1234
1234567899
Scheduled
Customer A
Customer B
Block 10
Nov-13

[Code] .......

This is a very large data set. The S/N will appear multiple times. The rest of the data will change with each entry, but there are some exceptions where it may be the same.

The second workbook has this data:
ID
S/N
A
B
P/N
Born-on-Date
Date Rec
Ship Date
Customer 1

123456
ABCD1234
1 thru 14
Yes or No
1234567899
03/10/2007
11/07/2013
11/22/2013
Customer A

[Code] .......

This too is a very large data set. What I need to do is to find the S/N in the first table "based on the month" and replace the entry under Customer 1 with the associated Customer 2 data entry. The VLOOKUP function can't seem to handle the multiple S/N entries.