...we have 2 webcams in our house for "security" (mainly to watch the dog/cat sitter while we are out of town). My dad just plugged them into the same computer (they are not literally hooked up "together" i don't think), and he uploads the picture to a website (that only our family knows). If we are out of town and at a computer we can login to that website, and see what is going on in our living room or in my dads office.
All he did was install the camera (through attic, 1 hidden in ceiling lamp looking down, 2 in my dads office) and software, and he takes the images that the software takes (or video, but that takes a while to download live over the internet). They are stored on the HD of the server, then the designated website takes the latest pic or video and updates the pic every 30secs i believe, and video streams i believe. It all seems pretty simple...but i am sure there is more to it.
Hope that helps...i really think it's convenient.