This one is a little confusing. Ok.. when you record a guitar track, can you play it back by pressing the play button in Sonar? We need to make sure that your audio is getting into the program first.

It is not recommended to use any on board sound card with Sonar. But of course it will play back audio if your willing to do a bunch or re-configuration of your audio.  If I disconnect my USB interface from my laptop, the wave files are all still there and they all look just fine, but, I would have to go into Sonars Audio preferences and change the whole shebang to my on boards MME driver etc , and change my master buss et before anything will play again. So I don't ever do this. Reason being, Sonar hates it and will cause me grief the next time I go to record using my proper ASIO interface. 
 
Just leave the Line 6 hooked up. Sonar will be happy and you will have no problems, unless the line 6 has crappie asio drivers or whatever. 
Before you record next time, make sure the tracks input is set to the line 6 and that the meters are showing a signal. 

Could it be possible that you are just arming for recording, not actually recording?

Yeah, I don't know what I did, but it seems to be working now.  I saved this time as a CWB file after using the POD HD500 as the record in and output.  Then I pulled the USB, closed Sonar, reopend Sonar, changed my drivers to the laptop sound card, and now I can see/hear all my guitar tracks fine.   I don't know if it was saving it as a CWB file or if I just did the right way this time, but we'll see.  Thanks for all the input guys! 

Cactus Music
It is not recommended to use any on board sound card with Sonar. But of course it will play back audio if your willing to do a bunch or re-configuration of your audio.  If I disconnect my USB interface from my laptop, the wave files are all still there and they all look just fine, but, I would have to go into Sonars Audio preferences and change the whole shebang to my on boards MME driver etc , and change my master buss et before anything will play again. So I don't ever do this. Reason being, Sonar hates it and will cause me grief the next time I go to record using my proper ASIO interface. 
 
Just leave the Line 6 hooked up. Sonar will be happy and you will have no problems, unless the line 6 has crappie asio drivers or whatever. 
Before you record next time, make sure the tracks input is set to the line 6 and that the meters are showing a signal. 
Thanks!  I figured that's best as well.  I tried the Eleven rack, HD500, and various plug-ins but keep coming back to the HD500 for ease of us and tons of free patches, and luckily it's a solid ASIO driver.  I'll just leave it hooked up from now on, since that's the only reason I even use the HD500 (recording quick stuff).  I'm slowly going to learn how to use this stuff properly.

Your HD500 is probably a better audio interface than your laptops built in audio interface, so you should keep on using the HD500 also after you have recorded....
 
As others here also mentioned, you should invest in a dedicated audio interface as soon as you have the opportunity. Now, in the beginning, the HD500 might be "good enough" for ya