Does anyone have any suggestions on what I should use as an anolog input? It should be something that I can mainpulate to see the variance on my output.
I think you need a little education about controls and feedback. It may not be as simple as you have described.
First, if you only want to manipulate "something", and see a result on your output (assuming the output goes to the speed reference input of your PowerFlex 4 variable frequency drive), then simply manipulate the Powerflex speed setpoint (using an analog output from your PLC, or a speed input from an HMI, or simply a potentiometer) from 0 to 60 Hz to see the VFD ramp from 0 to full speed. That is all you need to do what you described.
Now if you want to set up a typical feedback control loop, then you then will have to set up your VFD to "do something" in order to get some results to feed back into your PLC as an analog input. For example, if you connected your VFD to a fan motor, you could use the fan to cool down an object (or heat it up if you have duct heater or similar to blow some air through). Then put a thermocouple or temperature sensor on the object being cooled or heated, and feed that signal to an analog input. Use the analog input signal as a process feedback to control your VFD speed - as the cooled (or heated) object reaches it desired temperature, you could have the VFD reduce its speed until it maintains that temperature.
If you have a small pump available, you could hook your VFD to the pump motor, and use a flowmeter sensor to measure the flow through a hose, and use the flowrate signal to vary the speed of the VFD to maintain the flow at a certain setpoint.
A control loop is a system. Until you decide on your system, no one can tell you how to do something that is only a thought in your mind.
If anyone has a current program that I can view using such inputs and outputs, so that I can get a good understanding in how to program this, I would appreciate the help.
There are hundreds of programs posted on this site already. A search should find more than you will ever want to read through. Use search terms to find exactly what you are want. Click on "Search, Advanced Search" on the PLCtalk menu bar right above this post.
Here, I did a search for "beginner with analog outputs" to get you started. It found 6 old threads but no program examples. The last two threads are relevant to your beginning analog programs.
http://www.plctalk.net/qanda/search.php?searchid=3112363
I have dozens of program examples using analog inputs and outputs. I hesitate to post one, because it could only confuse you more. Most of the time, the parts of any control loop are spread out through a long routine. I will see if I can find a simple, concise, compact example. Here is one with the analog input and analog output in the same instruction in a 1-rung program.