Glad to hear you recently purchased BigFix… Hopefully you are happy with it so far…
You certainly can deploy the agent standalone… You can copy the file (either the client MSI or the setup.exe installer folder) to the computer and run it OR you can use the client deployment tool if that is a possibility. The BigFix Admin Guide has a pretty good section about options to deploy the agent and I recommend you look through that section to see the different options available to you: http://support.bigfix.com/resources.html