1.  Anon.  1966.  Marriage Index:  Ohio, 1789-1850.  Liahona Research, Orem, UT (Broderbund CD-400):  not found.

2.  1850 Census Index/Images (online at Ancestry.com; Image #153 of 472):  Amanda Twp., Dist. 48, Hancock Co., OH, p. 465B, 81/81, enumerated 7 Sep 1850 (extracted by Diana Gale Matthiesen):

Elijah Shoemaker	36	m	laborer	300
Mary	22	f
Charity	5	f
Elisabeth	4	f
Hiram	2	m

This census-taker wasn't wasting any ink.  Presumably, the blanks here mean Ohio, and we know Mary was born in Ohio.  Living next door to John & Matilda PLOTTS, who are living two doors down from Jackson & Elizabeth PLOTTS, who are living two doors down from Gershom & Mary A. PLOTTS.

4a.  AIS (Accelerated Index System) 1860 Census Index and 1860 Census Images (online at Ancestry.com):  there is an Elijah SHOEMAKER in Paint Twp., Fayette Co., OH (p. 846) and one in Clay Twp., Ottawa Co., OH (p. 77).  Neither one is our subject.  There was no Elijah SHOEMAKER in Michigan.  The Mary SHOEMAKER in Hancock Co. is not our subject.

4b.  Family Quest Archives:  Ohio Federal Census 1860:  Hancock County.  Heritage Quest CD M653-982:  Findlay Twp., Hancock Co., OH, p. 79A, 1117/1083, enumerated 13 Jul 1860 (extracted by Diana Gale Matthiesen):

Benjamin Stroub	58	M	United Br. Minister		1600	Pa
Elizabeth	57	F				"
[Benjamin & Elizabeth's unmarried children]
Elizabeth Shoemaker	15	F				O

Benjamin & Elizabeth (HAAS) STRAUB are Mary (STRAUB) SHOEMAKER's parents. 

4c.  1860 Census Images (online at Ancestry.com; Image #27 of 38):  Vanlue P.O., Amanda Twp., Hancock Co., OH, p. 210A, PN 27, 196/189, enumerated 8 Jun 1860, official enumeration date 1 Jun 1860 (extracted by Diana Gale Matthiesen):

Frederick Benner	63	M		Farmer	3300	300	Germany
Catharine   "	52	F					O
[Frederick & Catharine's unmarried children]
Hiram Shoemaker	11	M					"

Mary (STRAUB) SHOEMAKER's brother, Benjamin STRAUB, Jr., was married to Rebecca BENNER, daughter of Frederick & Catharine (MOYER) BENNER. 

5.  Library of Michigan 1870 Census Index and Images (online at the Library of Michigan web site):  not found.