How can I place five tables on a page, in a 3x2 matrix?
You can put the tables into minipages or parboxes or use the subfig package. Just remember that you can't put multiple table environments together, but you can put multiple tabular environments (with captions and labels) within a single table environment. The subfig documentation has information about both techniques.
Here's an example using both parboxes and minipages
\documentclass{article}
\usepackage[margin=1in]{geometry}
\usepackage{booktabs}
\begin{document}
\begin{table}[htbp]
\centering
\parbox{.45\textwidth}{
\begin{tabular}[t]{lll}
\toprule
A & B & C \\
\midrule
0.096356125 & 0.126535287 & 0.222951743 \\
0.011227006 & 0.154678302 & 0.134139901 \\
0.695793117 & 0.287078523 & 0.077578477 \\
0.325214308 & 0.069604001 & 0.657673026 \\
\bottomrule
\end{tabular}
\caption{ABC}
}\bigskip
\parbox{.45\textwidth}{
\begin{tabular}[t]{lll}
\toprule
D & E & F \\
\midrule
0.692628962 & 0.676885786 & 0.714726267 \\
0.216724956 & 0.514742162 & 0.274775702 \\
0.520019549 & 0.506134903 & 0.293514122 \\
0.186925802 & 0.285319488 & 0.403563324 \\
\bottomrule
\end{tabular}
\caption{DEF}
}\bigskip
\parbox{.45\textwidth}{
\begin{tabular}[t]{lll}
\toprule
G & H & I \\
\midrule
0.037156909 & 0.76115364 & 0.238202162 \\
0.086680665 & 0.028714787 & 0.879055353 \\
0.302193464 & 0.157574379 & 0.948781632 \\
0.503584342 & 0.885553012 & 0.30105766 \\
\bottomrule
\end{tabular}
\caption{GHI}
}\bigskip
\parbox{.45\textwidth}{
\begin{tabular}[t]{lll}
\toprule
J & K & L \\
\midrule
0.652587435 & 0.812241976 & 0.816788302 \\
0.456616676 & 0.320706153 & 0.882116653 \\
0.616582591 & 0.361915305 & 0.772590298 \\
0.78771219 & 0.53200612 & 0.564641396 \\
\bottomrule
\end{tabular}
\caption{JKL}
}
\parbox{.45\textwidth}{
\begin{tabular}[t]{lll}
\toprule
M & N & O \\
\midrule
0.733808918 & 0.699601932 & 0.11500169 \\
0.873043748 & 0.12076117 & 0.682781587 \\
0.918180185 & 0.63535945 & 0.445837393 \\
0.417373347 & 0.731406679 & 0.669593201 \\
\bottomrule
\end{tabular}
\caption{MNO}
}
\parbox{.45\textwidth}{\ }
\end{table}
\begin{table}[htbp]
\centering
\begin{minipage}{.45\textwidth}{
\begin{tabular}[t]{lll}
\toprule
A & B & C \\
\midrule
0.096356125 & 0.126535287 & 0.222951743 \\
0.011227006 & 0.154678302 & 0.134139901 \\
0.695793117 & 0.287078523 & 0.077578477 \\
0.325214308 & 0.069604001 & 0.657673026 \\
\bottomrule
\end{tabular}
\caption{ABC}
}\end{minipage}\bigskip
\begin{minipage}{.45\textwidth}{
\begin{tabular}[t]{lll}
\toprule
D & E & F \\
\midrule
0.692628962 & 0.676885786 & 0.714726267 \\
0.216724956 & 0.514742162 & 0.274775702 \\
0.520019549 & 0.506134903 & 0.293514122 \\
0.186925802 & 0.285319488 & 0.403563324 \\
\bottomrule
\end{tabular}
\caption{DEF}
}\end{minipage}\bigskip
\begin{minipage}{.45\textwidth}{
\begin{tabular}[t]{lll}
\toprule
G & H & I \\
\midrule
0.037156909 & 0.76115364 & 0.238202162 \\
0.086680665 & 0.028714787 & 0.879055353 \\
0.302193464 & 0.157574379 & 0.948781632 \\
0.503584342 & 0.885553012 & 0.30105766 \\
\bottomrule
\end{tabular}
\caption{GHI}
}\end{minipage}\bigskip
\begin{minipage}{.45\textwidth}{
\begin{tabular}[t]{lll}
\toprule
J & K & L \\
\midrule
0.652587435 & 0.812241976 & 0.816788302 \\
0.456616676 & 0.320706153 & 0.882116653 \\
0.616582591 & 0.361915305 & 0.772590298 \\
0.78771219 & 0.53200612 & 0.564641396 \\
\bottomrule
\end{tabular}
\caption{JKL}
}\end{minipage}
\begin{minipage}{.45\textwidth}{
\begin{tabular}[t]{lll}
\toprule
M & N & O \\
\midrule
0.733808918 & 0.699601932 & 0.11500169 \\
0.873043748 & 0.12076117 & 0.682781587 \\
0.918180185 & 0.63535945 & 0.445837393 \\
0.417373347 & 0.731406679 & 0.669593201 \\
\bottomrule
\end{tabular}
\caption{MNO}
}\end{minipage}
\begin{minipage}{.45\textwidth}{\ }\end{minipage}
\end{table}
\end{document}
resize the tabulars that three fit in one row:
\documentclass{article}
\usepackage{booktabs,graphicx,blindtext}
\begin{document}
\blindtext
\begin{table}
\centering
\minipage{0.32\textwidth}
\resizebox{\linewidth}{!}{%
\begin{tabular}{lll}\toprule
A & B & C \\\midrule
0.096356125 & 0.126535287 & 0.222951743 \\
0.011227006 & 0.154678302 & 0.134139901 \\
0.695793117 & 0.287078523 & 0.077578477 \\
0.325214308 & 0.069604001 & 0.657673026 \\\bottomrule
\end{tabular}}
\caption{ABC}
\endminipage\hfill%
%
\minipage{0.32\textwidth}
\resizebox{\linewidth}{!}{%
\begin{tabular}{lll}\toprule
A & B & C \\\midrule
0.096356125 & 0.126535287 & 0.222951743 \\
0.011227006 & 0.154678302 & 0.134139901 \\
0.695793117 & 0.287078523 & 0.077578477 \\
0.325214308 & 0.069604001 & 0.657673026 \\\bottomrule
\end{tabular}}
\caption{ABC second}
\endminipage\hfill%
%
\minipage{0.32\textwidth}
\resizebox{\linewidth}{!}{%
\begin{tabular}{lll}\toprule
A & B & C \\\midrule
0.096356125 & 0.126535287 & 0.222951743 \\
0.011227006 & 0.154678302 & 0.134139901 \\
0.695793117 & 0.287078523 & 0.077578477 \\
0.325214308 & 0.069604001 & 0.657673026 \\\bottomrule
\end{tabular}}
\caption{ABC third}
\endminipage
\bigskip
\minipage{0.32\textwidth}
\resizebox{\linewidth}{!}{%
\begin{tabular}{lll}\toprule
A & B & C \\\midrule
0.096356125 & 0.126535287 & 0.222951743 \\
0.011227006 & 0.154678302 & 0.134139901 \\
0.695793117 & 0.287078523 & 0.077578477 \\
0.325214308 & 0.069604001 & 0.657673026 \\\bottomrule
\end{tabular}}
\caption{ABC forth}
\endminipage\space%
%
\minipage{0.32\textwidth}
\resizebox{\linewidth}{!}{%
\begin{tabular}{lll}\toprule
A & B & C \\\midrule
0.096356125 & 0.126535287 & 0.222951743 \\
0.011227006 & 0.154678302 & 0.134139901 \\
0.695793117 & 0.287078523 & 0.077578477 \\
0.325214308 & 0.069604001 & 0.657673026 \\\bottomrule
\end{tabular}}
\caption{ABC fifth}
\endminipage%
\end{table}
\end{document}