Excel 2007 : How can I count rows from another file that meet certain criteria?

Background:
I have two spreadsheets, they are seperate files. Spreadsheet A (job locations) has a list of open job positions. Spreadsheet B (applicant list) has a list of all the applicants to all the jobs. If an applicant on Spreadsheet B has been accepted, a column on Spreadsheet B is populated with a number greater than zero.

Spreadsheet A identifies open job positions by city (ex. Tampa) while Spreadsheet B identifies job applied to by state code and city (ex. FL - Tampa).

Question:
How can I count the total number of applicants from Spreadsheet B that have been accepted at each individual job location (and display that number in Spreadsheet A next to the appropriate job location)?

Thanks for your suggestions and help!!!


Bonus questions:
Is it even possible to reference a cell range from another file within a formula?
Is there an online cheat sheet/flowchart demonstrating/explaining this kind of complex nested excel logic?


Solved by Friend:
=COUNTIFS([Spreadsheet B.xlsx]Sheet1!A1:A100, "="&C1, [Spreadsheet B.xlsx]Sheet1!B1:B100, ">0")

where:
[Spreadsheet B.xlsx]Sheet1!A1:A100 is the range of the city/state codes
C1 is the city/state code in spreadsheet a
[Spreadsheet B.xlsx]Sheet1!B1:B100 is the range of that number greater than zero that indicates acceptance