Rachel,
1881 census information is on the FamilySearch site at:
http://www.familysearch.orgTo get 1891 census information, I guess one would need to be an Ancestry subscriber - which I'm not so can't help with the reference number.
I still can't find the marriage of Arthur & Harriet, nor have I yet found either of them in 1881.
To summarize (and to indicate who might be expected to be found in 1901):
Arthur Petchell BARNES, birth Mar qtr 1860, Aylsham V4b, P91
Arthur Petchel BARNES death, age 39, Mar qtr 1900, Smallburgh V4b, P61
Harriett (surname?) - birth (Norwich ca 1862 from 1891 census) still to be found
Harriett BARNES death, age 49, Jun qtr 1911, Smallburgh V4b, P31
Arthur BARNES m Harriett (surname?) - still to be found.
Children (based on the 1891 census):
*Helen Emily BARNES
Birth Dec qtr 1882, Norwich, B4b, P1{56}6
(looks like 156 to me)
*Beatrice Kathleen BARNES
Birth Dec qtr 1885, Norwich, V4b, P173
*Mildred Sophia BARNES
Birth Mar qtr 1888, Smallburgh, V4b, P64
*Edith Annie BARNES
Birth Dec qtr 1889, Smallburgh, V4b, P55
*Albert Arthur BARNES
Birth Mar qtr 1891, Smallburgh, V4b, P53
- presumably the following death, Albert Arthur BARNES, age 1, Mar qtr 1892, Smallburgh V4b, P69
JAP