I found Sony Vegas pro 12 to a be a HUGE upgrade to prior versions in smoothness, speed, lack if crashing etc.
In a nutshell toss the pieces into the timeline, pan one source hard right and one source hard left then get a kinda close sync around a loud prominent sound (a first snare drum hit to begin a song is a nice cue), now maximize the height of the two sources and zoom in to the nice cue you selected (good idea to drop a marker here), visually align the cue sound and then listen (you can slow down the speed of the paly in the lower left corner if that helps), now zoom in a little more and visually align a little better and listen again, repeat till perfect.
HINT: only move one clip (whichever one is shorter)
HINT TWO: place your longest, most complete clip in the top line of the project, pan it hard left and compare all other clips to this reference clip
HINT THREE: do NOT join audio or video clips in another program first, this sucks but most devices drop a few frames between clips, if you join them they look fine but if you play them against a continuous source they don't match properly, do all your alignment in vegas, for me the Sony M-10, does not drop samples, the editrol does (about 3.5-3.75 frames) and the Sony and Panasonic cams do (my panny drops exactly three frames at each split, about a twentieth of a second).
HINT FOUR: save a lot with new file names, so if you botch something, you can go back to a prebotch save without wondering what is what
Dave