Welcome to TeX SE! The problem is that you are mixing two different ways of managing citations and bibliography. One is to use \cite{} etc. and thebibliography. The other is to use biblatex with a database of bibliography entries and \printbibliography.
Here's one way of doing it which uses biblatex/biber with an external .bib file of entries. (The filecontents environment just creates the external .bib file.)
\documentclass[11pt]{article}
\usepackage[backend=biber]{biblatex}
\bibliography{\jobname}
\begin{filecontents}{\jobname.bib}
@book{lit1,
author = {Author, A. N.},
title = {Title},
publisher = {Publisher},
address = {Location},
year = {1066}}
\end{filecontents}
\begin{document}
This is the text from some book. \footfullcite{lit1}
\printbibliography
\end{document}

This is just for purposes of demonstration: you wouldn't normally want a full citation in the footnote and a separate bibliography. Although I have seen undergraduate submission requirements which actually demanded just this.
Another way, As Andrew Swann suggested is to use
\usepackage[backend=biber,style=authoryear]{biblatex}
with the \footcite{lit1} which would give

Or you can use \footfullcite{} and simply remove the \printbibliography command if you don't need a separate bibliography.
.bibfile for the publications and processing withbiber. Then you can specify anauthoryearstyle. – Andrew Swann May 04 '15 at 14:00