I can't find where to keep notes about the project i'm working on, can you not do this with Sonar X2?

In older versions of SONAR it's File->Info, in recent versions (X onwards) it's Project->Info

Choose Project > Info
 
There are also other places to take notes, e.g., in track view.

In addition to Project > Info,SONAR provides text fields in folders, tracks and take lanes

A trick I always use....
 
I have a dummy midi track (it does not send midi to anything in Sonar, just a old piano module that I can hear thru my analogue mixer if I choose) with scratch melodies and chords.  I view this in Staff View.  When composing I can write myself notes in staff view using the "expression" lane...like "last Verse, Take strings Up an Octave"...or "see if Harry can sing this better than Bob"
 
Of course I do this with Markers also,  but that gets too crowded usually.     

Good idea jumbo!!