The LANDesk Agent is configured (and can be built into a self-contained executable) on the Core Server. This is assuming you have a Core Server? It's not something "you download" from here / someone else provides you externally. It relates to YOUR company server(-s) and has YOUR specific certificate(s) included in it.
In regards to how to configure / build the agent, I'd suggest you check the following section of the community -- Agent Deployment .
The following articles may be of particular use to you:
That should be a solid starting point I believe.