It doesn't matter if there's an address or no. The important informations on the letter are:
"Basically, your employer letter should state "To whom it may concern: (first name,last name) has been employed
full-time with the XYZ Company since 200_ as a (name of your job), and is an employee in good standing with an
annual salary of $XXXX. Signed, John Doe, Supervisor (or whatever title)" The letter should be on company
letterhead." (http://www.visajourney.com/content/support)
(does not need to be stated exactly like this, for sure)
But as it will be needed for the interview at the embassy, it can be addressed to the US Embassy, yes.
Most important is showing proof that you have been together within the past 2 years. Visa stamps on your passport, and such. But as long as you have enough of the other "good stuff" 5 pics should suffice.
Erynn reacted to didopage in Letter from the Employer