Where are people interested in business to be found?

For just 2 - 3 years ago it was great to post on forums with a signature link to a website just after a few hours orders came in. During the last years this has changed it has been much more difficult to get traffic / orders to a website by forum posting.

Now I was wondering where are these people? Do they stick around on Facebook and if so where?

Or are there other medias like LinkedIn? I never had any success with LinkedIn too complicated to setup and to advertise there!