To make a receiver go to create player and create the player as a quarterback. Give the player very low passing abilities (zero) and very high catching and ball handling levels. The player will cost very little because his quarterback skills are bad. You will have to sign him as a quarterback but use him as a wide receiver. His salary will never go up because he will not play as a quarterback. You can also change his number and attributes in the edit player screen. You can also make a dirt cheap fullback by eliminating his receiving skills.