Problems recording Guitar into Sonar X1 Producer.

What you are dealing with is the latency issue that any computer recording software has to deal with. The quick fix is to move the audio clip backwards or forwards until it sits in the track just right. The long fix is trying to adjust the buffer settings until you get the latency within an acceptable range. Sometimes it takes a while to find a setting that is acceptable to you. And don't worry! ALL DAWs suffer from this.
You will find tons of discussions on all the DAW forums about latency. If you don't know what it is just launch a search about the topic. The simple fast answer is latency is the amount of time it takes for your signal to go from the input on your soundcard thru the computer and software for processing and out the output.

+1 on looking for latency.  You can go into the Sonar Preferences and see the reported latency values.
 
For MY system, I use a dedicated audio interface and my settings and reported latency values are:
 
Interface: Sample Rate = 48 k, ASIO Buffer Size = 128
Sonar: Driver Mode = ASIO, Sample Rate = 48 k (must match interface)
 
Reported Latency Values in Sonar Preferences:
 
Input:   4.7 MS, 224 Samples
Output: 4.7 MS, 224 Samples
Total Round-Trip: 9.3 MS, 448 Samples
 
I would suggest you shoot for something at or under 10 milliseconds of total round trip latency.
 
Also, I suggest you monitor through Sonar, rather than with any direct monitoring from your interface, as ANY DAW will introduce some level of latency.
 
Hope that helps, 
 
Bob Bone