\documentclass[11pt,a4paper]{report}
\usepackage[spanish]{babel}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}

\usepackage{booktabs}
\usepackage{tabulary}

\begin{document}

\begin{table}[htbp]
\centering
\begin{tabulary}{13cm}{CCC}
\toprule
\textbf{Producto} & \textbf{Volumen} & \textbf{Precio}  \\ \midrule
Detergente ``pepito'' & 5 l & 3500 pts \\ \midrule
Lavavajillas ``juanito'' & 1 l & 130 pts  \\ \midrule
Manzanas rojas  & 0.150 l & 75 pts \\ \midrule
Jamón 30 Js  & 7 l & 25000 pts  \\ \midrule
Bolígrafo ``Acme'' & 0.010 l & 150 pts \\ \bottomrule
\end{tabulary}
\label{tbl:ejemplo}
\caption{Una tabla de ejemplo con tabulary}
\end{table}

\end{document} 
