Agilent has a plug and play driver that you can download
here. A plug and play driver is created with LabWindows/CVI and can be converted to a LabVIEW driver from the Tools>Instrumentation>Import CVI Instrument Driver menu. A plug and play driver is perfectly usable but you won't be able to modify the driver code unless you have LabWindows/CVI. NI has a traditional LabVIEW for the 8712B that you can download
here. I don't know what the difference is between the 8712B
and 8712ET. I would suspect that they're minor as regards to programming. Both drivers use VISA and you should be able to use TCP/IP to communicate with instrument assuming that you've got one of the more recent versions with TCP/IP support.