I concur with all these great insightful suggestions
May be some more tips:
Answers to these questions would help you get a clarity
for your lead generation strategies
a. Your ideal target audience or ideal target customer
(dont be everything to everybody-- you can have clusters but better to focus on one or two profitable groups
b. What has been your free promotion material that brings in the foot falls
c. have you identified the Top 3 problems the face while they outsource their video production to you
d. How do you solve them differently when compared to your compettitors
e. Do you know how do they reach out and select a video production company --- How do they buy
f If you have identified these 3 problems -- have you put them in your communique Does that resonate with them

g. Do some data mining (as you have tried FB,Google etc
What has worked in the past--- Who is your ideal target customer How big is this market and how do you communicate and get them on board
h. What products do you have for upselling or cross selling or backend selling-- if you already have a steady base
i: Offer some thing radical that is not being offered by your competitors
j: Do you have a "Customer Delight Program" so that you can get referrals and testimonials from your happy customers

Hope that helps
All the best
BP
Business Growth Specialist
Chartered Marketer UK
vibavam.com

Armed with that ideal customer, either do the research yourself--digging through websites and resources--or buy a list with some specific parameters.

Many valid and insightful suggestions already.

Your requirement is "How to address them"
The simplest formula is this:

a. What is your target audience or who is this (can you group them)
b. Which problem of theirs do you solve? (or your product solves)
c. Add an active verb of the action
Example: An attorney who focusses on Divorce

a. Couple having marital problems
b. Looking for a speedy and freedom with no headache
Intro: I help unhappy couple settle amicably in shortest span of time

Intro of a Printer focusing on Small businesses:
I help small businesses sell more through my creative and cost effective printing materials

Some more tips:
a. Get to know their problems and focus on the top 3 problems
Can you create a "Do it yourself" material and help them solve these problems?
It can be distributed as a free download on your website
Or a Free Counselling could even help

If your work started yielding results then create stories of success---
Stories that is embedded with Testimonials
How did it help them --so to say
We can have a free ten minutes of call if required
All the best
Business Growth specialist
Chartered Marketer UK
vibavam.com

Great answers already.
Some of my tips
1. What techniques got you so far? Can you standardise it
and check it if the same works in the US market
2. Would it be possible to draw up referrrals in the US markets
3. Producing consistent quality content on your website and be aggressive with your solid social media strategy.
4. Check with your digital agency to create "some useful and relevant content" that can go viral in the social media-- specifically USA market
5. Do you have affiliates from the US?
6. What part of the product can be given free as a "Test material" It can even be a "service tips" material Let them have a feel of your product and your service -- in short your brand
7. Can you participate in any trade shows physically or online
8. After creating all of these you could promote and advertise for "Distributors, Affiliate Partners " in that region

I can give a 10 minutes free talk in this regard

Hope it helps
Consultant Bala
vibavam.com

Hello
Great answers already but still thought of adding few more points

1. Are you part of any network particularly on the innovation side I am a fellow indian check out national innovation foundation
2. As much as there are problems in India-- it provides greater opportunities as well Which of the industry or products can your mecnanical engineering can be put use into
3. Have you thought of servicing as a product?

4. Lastly how about teaching or handholding new engineers with their projects (last semester projects)
In fact you can startup some thing (like servicing) with these engineering students as your apprentice for all of your servicing projects
I can help you with further ideas and spare a 15 minute talk

Thanks
Consultant Balaji
Chartered Marketer UK