The first number of the SPSET command is the control number. By using SPSET 1,0,0 for example, you would create a second Sprite with a control number of 1.
To change the position, use SPOFS. A SPOFS command could look like this:
SPOFS 0,X,Y
First number is the control number, the next two numbers control the X and Y position. You can just put numbers in place of those, or variables...