How do I detect collision on my lan network?

This information is usually buried in the status information or logs of managed network hubs, indicated by diagnostic lights on unmanaged hubs, and in the software utility of network adapters.

Note the key word that Sleros is using: HUBS. By design, hubs are collision domains whereas switches are limited on a port by port basis.

Are you looking for all types of error data perhaps? Drops, retransmits, allignment errors, etc. This information can easily be accessed if the device is managed with a telnet session.