How do I determine if the Electronic Sound Packs were installed? Where are they?

Since you are new here Mike.... WELCOME!!! 
 
If it's Cakewalk Sound Center packs... you will see them when you open the CSC synth and look at the menu drop down listing the instruments. They should automatically appear in that list.
 
You are going to like this program if Atari and Mac are your past experiences.  Be patient, because there is a learning curve to this software.  There's some good folks here who will help. Just ask specific questions.
 
First, list the computer/OS you're using and the sound card... specs are appreciated. That lets us know about the rig you have.
 
Working with synths, you will very likely need to purchase an aftermarket MUSICAL INTERFACE ... simply a fancy name for a soundcard that can handle the job.  Factory soundcards generally do not work well with synths and exhibit unacceptable latency.
 
Have a look here to see how to set up a synth to work: http://www.herbhartley.com/hh2_edited_slimmer_005.htm  
If you have questions, don't hesitate to ask.  
 
Essentially, and this is very basic synth/midi stuff.... a synth requires 2 different tracks that are linked. 
 
You  simply select the Instrument track ( I think that's what it's called..... I don't often use midi) option and both tracks will be set up automatically for you and linked. You choose the synth you want from a drop down list and set any channels if they are needed and you're not using MIDI OMNI.
 
If you don't select a synth, you will not hear any music. If everything is set up properly, you should hear sound.
 
If Sampletank is not showing up in the synth's dropdown list, you may need to add it manually using the plug in manager.
 
Just advise us what progress you make.   Good luck and be patient. It took me the better part of 2 weeks to get my system working. But one day, I pressed a key and waaa laaa..... sound.... nothing has ever been the same since. I totally enjoy this hobby....
 
 
 
 

Good...  post some music when you get the chance.

Welcome to the forum Chuck.
 
You might get better responses to your question if you start a new thread.  Tacking an unrelated question to an unrelated post is called 'hijacking.'
 
To install license keys you must be logged onto your computer as an administrator.  Keys are stored in an area that requires special permissions that the Admin account has.  Once the keys have been entered (using the Administrator account) you can access the application using a regular user account.
 
Glen