Marty,
I shouldn't bother ordering anything yet. Just post another lookup here with "Lookup Witham HO107/1783/81". Sorry my fault, I forgot to give you the reference for Witham as I was beginning to lose concentration.
At the same ref as William are:
MEAD HANNAH 10 KELVEDON ESS 81 KVD
MEAD MARIA -3 KELVEDONESS 81 KVD Age of -3 means 3 months
MEAD MARK W. 19 KELVEDON ESS 81 KVD
MEAD MARTHA P.36 KELVEDON ESS 81 KVD
MEAD WILLIAM 45 KELVEDON ESS 81 KVD
KVD stands for Kelvedon. ESS for Essex. Look at the headings of the first mail I wrote for Tendring to get the idea.
So that is PROBABLY your William Mead age 45, his wife Martha P age 36, daughters Hannah age 10, Maria age 3 months and son Mark W age 19. They were all born in Kelvedon (Witham area) and live there at the time of the 1851 census. Because there is such a big age gap I would assume there are other children in between. Boys also tend to go off to work or boarding school. Girls usually stay home! VERY sexist but that's what used to happen. There was also an extremely high infant mortality rate(~40% for poorer families).
All the other info is my working and they may possibly(?) be related to your people so worth keeping for the future.
The next thing I would do is look at LDS website for these new names ("relations") and also FreeBMD at
http://freebmd.rootsweb.com/cgi/search.pl so you might be able to cross-reference in order to find the birth/marriage/death certificates and go back further.
Have a look at the Beginners section for tips!
Good hunting,
Geoff.
PS If you order anything, you want the 1851 Witham or full Essex census for the actual page with above ref (check the cost!) to just gain the address where they live and their occupations.