I think that this must be your William, but I have tentatively put him as the son of Samuel Bowman of Grayson County, VA.
If it is your William & you want, I can also port later census abstracts.
WILLIAM BOMAN – ELISHABETH THOMPSON
2 Feb 1826 Grayson Bond1826-4: William Bowman and Elizabeth Thompson, daughter of Henry Thompson of Montgomery County; George Bowman and William Lawson Sureties.
Return 3-33: unsigned, certifies the marriage of William Bowman & Elizabeth Thompson of Feb 2, 1826.
[George Bowman was probably acting as a brother as he was about the same age. I think both were sons of Samuel Bowman.]
1830 Patrick County VA census (1 June 1830 through 1 June 1831)
William Bowman 2 males < 5, 1male 30-40, 1 female 20-30
[These two boys are presumably Anderson & Austin]
The 1835 Grayson County Virginia
Personal Property Tax List
Name /Tithes/Blacks12-16/Blacks 16+/Horses/Tax
Bowman, William /1/ --/ -- /1 /.06
Boman, Samuel /1 /--/ --/4/ .24
1840 Grayson County VA Census The 1840 Grayson County, Virginia Federal Census - Eastern District
(New River Notes http://www.newrivernotes.com/va/grayson1840east.html
Samuel Boman: males; one 5-10, one 10-15, two 15-20, one 50-60, females; one 10-15, one 50-60.
William Bowman: males; one under 5, three 5-10, four 10-15, one 30-40, females; one 5-10, 1 40-50.
1850 Patrick County VA Census
William Bowman (H#363,F# 383) $300 real estate c1810, Elizabeth Bowman c1815, Anderson Bowman, c1826, Austin Bowman c182, John Bowman c1833, Elias Bowman c1835, Eliza Bowman c1837, Calvin Bowman, c1838, Rankin Bowman, c1840, Henry Bowman c1841, Susan Bowman c1843, Franklin Bowman c1845. All born in VA.
1860 Patrick Count VA Census, North Division
William Bowman (H# 56, F# 58) $500 real estate 58, Elisabeth Bowman 58, John Bowman (died 1862*). 28. Crocket Bowman 22, Eliza Bowman 24, Susan Bowman 15, Franklin Bowman 13, Ruth Bowman 3 (died 1861*), Lucy Thompson 96. All born in VA
*John Bowman so William and Elizabeth Bowman DOD 13 Aug 1862 A 28, fever, single
*Ruth Bowman do William and Elizabeth Bowman DOD 24 Nov 1861 A 4, Diptheria, informant Susan Bowman, friend