Sculptures, drawings and engravings: 
The Torah prohibits making a sculpture and engraving certain items which resemble the spiritual legions of Hashem. Some of these items are even forbidden to be drawn. In Halacha A the law of drawing forms in the Madurei Elyon [Celestial legions] will be discussed. In Halacha B the laws of forms in the Madur Tachton [world creations and legions found in our heavens] will be discussed. In Halacha C the general law of making an incomplete form of the above will be discussed. In Halacha D owning such a form will be discussed.
Making a sculpture, engravings of a human:
Human body: It is forbidden to form a sculpture of the human body even individually [without the other faces of the chariot]. [Some Poskim rule it is forbidden to make a human sculpture even if one adds to it only one or two of the faces of the chariot [or other faces]. Other Poskim however rule it is permitted to make the human body together with other faces, so long as one does not make all four faces of the chariot. If one makes the human body together with the other three faces of the chariot he possibly transgresses two negative commands.]
Making for beauty and decoration purposes: It is forbidden to make any of the above forbidden forms even for purposes of mere beauty and decoration.
Incomplete sculpture of a human: There are Poskim who rule that the entire prohibition against forming a human sculpture is only if the form is whole and complete with all its limbs. However, it is permitted to form or own an incomplete sculpture of a human body, such as only a head or only a body without a head. Practically, so is the custom. [Likewise, it is only forbidden if it contains two eyes and a complete nose and the entire body is sculptured or engraved. Other Poskim however rule that even half of the body, or just the face, is forbidden to be sculptured. Accordingly, those Menorahs that contain sculptures of half a body must have their figure destroyed. Practically, one who is stringent in all this is blessed. However, one is not to protest those who are lenient. ]
May one make/manufacture Sheitel heads?
Some Poskim permit doing so being it is not a complete figure. Other Poskim are stringent as stated above. Practically, one is not to protest against those who are lenient although some are stringent to leave out some part of the face, such as the nose and the like. Regarding buying and owning the above items-see B in Q&A!
If a human sculpture was made by an idol worshiper and then given to a Jew it is [Rabbinically] forbidden for the Jew to keep the sculpture in his possession. If one found a human sculpture, then it is permitted [in benefit] so long as it is not a sculpture that is commonly worshiped by the gentiles. It is however [Rabbinically] forbidden for this sculpture to remain in one’s possession [and hence must be sold off]. [Some Poskim however rule it is permitted to buy and own all sculptures that are no longer customarily worshiped. Based on this the widespread custom is to allow owning human sculptures.]
May one buy and own Sheitel heads?
 Michaber Y.D. 141:4; Rosh Hashanah 24a
 Shemos 20:20; Chinuch Mitzvah 331
 Michaber ibid; Avodas Zara 43b
 The reason: This is learned from the verse “Lo Sasus Iti” which is read Osi, do not make Me. Now, since Hashem at times appears like a human before the prophets therefore He prohibited making sculptures of the human body. [Shach 141:21; Taz 141:11; Avoda Zara 43b]
 Taz ibid
The reason: Although when one makes a human face without all three other faces there is room to argue that it should be permitted, as he has not made a lone human face and has also not made all four faces, nevertheless, it remains forbidden due to the human face which may not be made even individually. So is proven from the fact the Poskim did not write of such an allowance. Nevertheless, in the event that the sculpture was already made with one or two of the other faces it suffices to chip simply the human face and one is not required to chip the other faces. If, however all four faces were made then one would be required to chip all four faces. [Taz ibid]
 So is implied from Taz ibid, as the prohibition of human remains even when one adds more faces. Vetzaruch Iyun
 Shach 141:21 and Nekudos Hakesef in gloss on Taz ibid that the Rishonim discussed this matter; Ran; Tosafus Rosh Hashanah 24; Ramach, brought in Shach ibid and Kesef Mishneh on Rambam Hilchos Avodas Kochavim 3:11
 Shach ibid; Tosafus ibid
 Michaber 141:4; Rambam
 Michaber 141:7
 Rosh; Tur; Rabbeinu Yerucham
Other opinions: See continuation!
 Michaber ibid
 Rama ibid
 Shach 141:25
 Semag Lavin 32 brought in Shach 141:32; Taz 141:15 in name of Perisha, in name of Rashal, who brings in name of Semag that he is stringent even with a mere head; Maharit Y.D. 2:35 in implication of question of Ran ibid who did not answer that a mere head of a human is allowed; brought in Birkeiy Yosef 141 and Gilyon Maharsha 141:7; Kneses Hagedola 141:22, brought in Darkei Teshuvah 141:40 and 50; Yaavetz 1:170, brought in Pischeiy Teshuvah 141:10 rules that even according to the Rosh, only a plain face without eyes and without a body is valid, however a body with a face is invalid even if it does not have eyes, and likewise a face with eyes and a nose is invalid even without a body; Yaavetz 2:104, brought in Yad Efraim 151:4; Beis Lechem Yehuda ibid; Rav Poalim 4:10, in name of many Rishonim who argue on the opinions brought in Michaber ibid
 Shach 141:32; Shelah p. 73b, brought in Pischeiy Teshuvah 141:11
 Rav Poalim 4:10
 Michaber and Rama 141:7 as brought above
 Rav Poalim 4:10
 Taz 141/12
 Michaber ibid
The reason: As people may come to suspect the person. [Shach 141/23; Taz 141/9] Some say this means he may be suspected to have transgressed and made the sculpture. [Gr”a 141/21] Others say it means he may be suspected to be worshiping the sculpture. [Haemek Sheila 57/3 in name of most Rishonim]
 Shach 141/24
 Michaber ibid
 Taz 141/12
 Shach 141/24; Taz 141/10
 Haemek Sheila [Netziv on Sheilasos] 57/3;
 Haemek Sheila ibid; Yabia Omer 3/8; Yechaveh Daas 3/64; Halichos Olam 7/282
 The reason: As some Poskim [Michaber and Rama 141:7] rule the prohibition against making human sculptures does not apply to a mere head, and only applies when making a head with a body. Furthermore, even according to those Poskim who are stringent, that is only regarding making a sculpture of the head, however owning it is permitted even in their opinion being that today the suspicion that one may be using it as idolatry no longer applies. [Haemek Sheila [Netziv on Sheilasos] 57:3]
 See Beis David 74, brought in Darkei Teshuvah 141:32; Maharit 2:35, brought in Darkei Teshuvah 141:44; Erech Hashulchan 141:8, brought in Darkei Teshuvah 141:44; All Poskim who are stringent regarding owning coins and Menorah