Just to highlight a nifty command that is sometimes forgotten...
ALIGN (from 'Help')
You can move, rotate, or tilt an object so that it aligns with another object.
To align two objects
Click Modify menu 3D Operation Align.
Select the objects you want to align.
Specify the first source point and then the first destination point.
If you press ENTER now, the objects are moved from the source point to the destination point.
Specify the second source point, and then the second destination point.
Specify the third source point, or press ENTER to continue.
Specify whether you want to scale objects to the alignment points.
The objects are aligned (moved and rotated into position), and then scaled. The first destination point is the base point of the scale, the distance between the first and second source points is the reference length, and the distance between the first and second destination points is the new reference length.
Command line: ALIGN