When we talk about the Dark Web, we talk about TOR.
There are a few alternatives to TOR, but if you are researching brand abuse or plagiarism of your products, TOR is the best place to start with.
In the TOR network you will find Dark Web Market Places and Dark Web Chat Rooms in which you can search for the information you are interested in.

Seeing in the Dark

To access resources on TOR, you need an entry point to the TOR network. Our TOR Crawler uses the official TOR socks proxy to communicate with the TOR network.

The TOR proxy tunnels HTTP, HTTPS and DNS requests to the TOR network, where Onion URLs, the URLs of the TOR network, can be resolved and accessed. TOR is anonymizing the traffic in the TOR network, so that neither the identity or location of the requested resource nor the location or identity of the requesting ds9 server is known to anybody within the network.

The traffic from ds9 to the TOR Proxy does not leave the ds9 server and is therefore safe. The traffic from the TOR proxy to the TOR network is encrypted. Each of the three hops from TOR relay to TOR relay before the request is finally leaving the TOR network is adding a layer of encryption, building the encryption layers that gave The Onion Routing its name. Traffic from the TOR exit point to the requested resource may be unencrypted and could potentially be open for somebody to monitor.

TOR Crawler

The TOR Crawler works like an ordinary URL Crawler with the difference that it can deal with .onion URLs, the URLs supported by The Onion Routing. Links in the TOR network work in the same way as in the Surface Web or in the Deep Web. Since ds9 Crawlers are mostly used for targeted crawling (we do not want to let them escape into the World Wide Web) it is advisable to have a TOR Browser at hand to verify the crawled Onion URLs and be able to build regular expressions to extract content from pages in the Dark Web.

Note: Using the TOR Crawler in combination with some other crawler on the same websites could cause network traffic that could be used to break the anonymity provided by TOR. ds9 is doing a best effort to keep the ds9 server anonymous to keep it from being nosed out and potentially attacked by your targets in the Dark Web. Be aware that there is always a risk of leaking information through other resources that may lead to identification of the ds9 server.