I have two spreadsheets

The first lists URLs for several hundred companies along with the number of
email addresses associated with that company. This work sheet is called
"Domain"

Example

Column 1 Column 2
URL # of Users
abc.com 1234

The other lists company names, city and state locations and the URL for that
company. It is called "Blitz"

Example

Column 1 Column 2 Column 3 Column 4
ABC Company New York NY abc.com

I want to compare Domain and Blitz based on the URL. If a URL on "Domain"
is also located on Blitz, then I want to pull the number of users and
pre-populate a new column 5 in Blitz called "# of Users"

This way I can find out which companies in my area have the most number of
users.