1.  LDS.  Family Search: Internet Genealogy Service:  IGI - International Genealogical Index (online at FamilySearch.org).

Michael STREEP Spouse: Lydia SLACK Marriage: 15 Oct 1855, Muskingum, Ohio Source: Marriage Records, 1804-1917. Ohio. Probate Court (Muskingum County)

"STREEP" is a mis-reading of "STRUP."

2.  1850 Census Every-Name-Index/Images (online at Ancestry.com, Image #48 of 462):  Cincinnati (Ward 11), Hamilton Co., OH, Roll M432_691, p. B, 236/369, enumerated 20 Jul 1850, official enumeration date 1 Jun 1850 (extracted by Diana Gale Matthiesen):¤•

Gottfried Koehler	37	M		Cooper		Germany
Elizabith    "	30	F				"
Barbara      "	8	F				Ohio
John         "	6	M				"
Henry        "	4	M				"
Barbara Bopp?	60	F				Germany
Joseph Clever	20	M		"		"
Peter Reider	21	M		"		"
Michael Straub	23	M		"		"
George Hoff	18	M		"		"
John Koehler	26	M		"		"

We can't be certain this is our subject, but he certainly appears to be, and he's not in Jackson with his presumed brother, John.

3.  1860 Census Every-Name-Index/Images (online at Ancestry.com, Image #1 of 30):  Zanesville P.O., Town of Jackson, Washington Twp., Muskingum Co., OH, Roll M653_1018 (Book 1), p. 146B, 245/245, enumerated 22 Jun 1860, official enumeration date 1 Jun 1860 (extracted by Diana Gale Matthiesen):¤•

Michael Straup	33	M		Cooper			Germany
Lydia     "	28	F					Ohio
Charles   "	3	M					"
Susan     "	1	F					"

Listed next to John & Elizabeth STRAUB/STROUP.

4.  1870 Census Every-Name-Index/Images (online at Ancestry.com):  can't find.

5.  Archives of the OHMUSKIN mailing list (online at RootsWeb.com).  A post there gives a reading of SLACK marriage records in Muskingum County and spells Michael's surname, "STRUP."

5.  WorldConnect / Ancestry World Trees (online at RootsWeb.com/Ancestry.com).