I agree with the post. You can also ask your friends and colleagues to tell you if they know any good construction and demolition e-stores. Deal with those e-stores only which you have some experience with in one or the other way. Read the "About Us" content carefully. Read also the terms and condition too.
There are plenty of construction industries but sometimes you may get a feel of that there are not much in your area. They don't do much promotion and that is the reason why you may never come to know about them until you intentionally search for them.
The best way to find construction companies is the Google. Most of the companies use Google Map to show where they are situated. Find the construction companies by the related keywords and you find lots of links about them.