There are several options. What platform are you on - winows/linux/mac? What interface are you using - USB or GPIB via some sort of adapter? If you're on Windows, you can buy the exorbitantly expensive and cumbersome labview software. You could use the also exorbitantly expensive and cumbersome matlab. These are not the only options, though. There are free programs available that should be able to communicate over whatever interface you are using. If you are using the USB port directly, then you need something that can speak USBTMC. It is possible to install the NI VISA software in windows and linux and then communicate with that from C directly or from Python with pyvisa. Another option is the pure python python-usbtmc driver, which should run on anything that libusb runs on (tested on windows, mac, linux, and the raspberry pi). If you have a GPIB interface of some sort (either USB or PCI), then you're probably going to have to install the NI VISA software and then use C or Python via pyvisa.
In terms of environments, I would personally recommen Python as it is rather easy to learn and because it is interactive - you can start up the Python interpreter, import the instrument drivers, connect to the instrument, and send it commands without having to write up a whole program and compile it. If you have ever used Matlab before, it's more or less the same idea, except Python is an actual programming language that's not horribly unpleasent to work with.