Using biblatex is a very good idea but then you have to use a bib file.
The advantage is double: biblatex gives you a lot of parameters to define the layout of the bibliography and the bib file can be used for more than one LaTeX document.
You gave no concret examples for your book so have a look to this MWE (package filecontents is only used to include a example bib file in the mwe code; please notice that I used biber):
\RequirePackage{filecontents}
\begin{filecontents*}{\jobname.bib}
@Book{goossens,
author = {Goossens, Michel and Mittelbach, Frank and
Samarin, Alexander},
title = {The LaTeX Companion},
edition = {1},
publisher = {Addison-Wesley},
location = {Reading, Mass.},
year = {1994},
}
@Book{adams,
title = {The Restaurant at the End of the Universe},
author = {Douglas Adams},
series = {The Hitchhiker's Guide to the Galaxy},
publisher = {Pan Macmillan},
year = {1980},
}
@article{einstein,
author = {Albert Einstein},
title = {{Zur Elektrodynamik bewegter Körper}. ({German})
[{On} the electrodynamics of moving bodies]},
journal = {Annalen der Physik},
volume = {322},
number = {10},
pages = {891--921},
year = {1905},
DOI = {http://dx.doi.org/10.1002/andp.19053221004},
}
\end{filecontents*}
\documentclass{article}
\usepackage[utf8]{inputenc} % <========================================
\usepackage[T1]{fontenc} %
\usepackage[
backend=biber, % bibtex % bibtex or biber (prefered)
natbib=true,
style=numeric,
sorting=none % none, nty % no sorting or standard sorting
]{biblatex}
\addbibresource{\jobname.bib} % calls bib file to create the bibliography
\begin{document}
We first cite Albert Einstein~\cite{einstein}, second~\cite{adams} and
third the \LaTeX{} Companian~\cite{goossens}.
\printbibliography
\end{document}
With the option sorting=none the resulting bibliography follows your cites as you can see here:
Now only with changing the biblatex option sorting=nyt the resulting bibliography is sorted by the author names.
See here:

The order of the bib entrys in the bib file do not change the results.
Just a remark: You saw the character ö in my example bib file? That's the reason I used utf-8 encoding (line 35 of MWE). Then you should use biber, which can handle utf8 encoding.