Find registered domains containing keyword

I need to contact domains that contain certain keyword.
Once I get those domains, if they meet my criteria, I wish to offer them my products and services via email.
For example, domains that contain city name. Let's say Boston.
What is the best way to find these types of domains?

Buy scrapebox and watch the video

https://www.youtube.com/watch?v=LyCLfL_ffqQ

Local directory if exists and search engine .

inurl:"boston" on google maybe ? it checks all the url not only the domain name but it could help you i guess
or something like this : inurl:"*boston*.com" maybe

Thank you all for replying.

at rashow
Your suggestion is giving decent results.

at wblteam
I've already tried some local directories.
The problem is that some of them require registration in order to see community members.
That would be ok if they required only email and user name, but some insist that you have to be local blogger in order to register.
In other words, they require you to leave a website address that is manually reviewed.

at alexel
How would you rate Scrapebox from 1 to 10 in terms of:
- Performance (time spent and results compared to free online tools and manual search)
- User interface intuitiveness
- Value for money

btw. It's a bit annoying not being able to post domain address, at symbol or an image in your post as a newbie.