A slight modification of Keks' answer. You could use phantomsection to avoid introducing blank pages. You will have to specify the section title for table of contents separately using \addcontentsline{toc}{section}{<title here>}.
\documentclass{article}
\usepackage{pdfpages}
\usepackage{hyperref}
\begin{document}
\tableofcontents
\phantomsection
\addcontentsline{toc}{section}{doc1}
\includepdf[pages=-]{document1}
\phantomsection
\addcontentsline{toc}{section}{doc2}
\includepdf[pages=-]{document2}
\end{document}
However in the above example you can only link to first page of the pdf file.
One way to link to pages within the pdf would be to add the pdf file in pieces,
\phantomsection
\addcontentsline{toc}{section}{doc3}
\includepdf[pages=1-5]{document3}
\phantomsection
\addcontentsline{toc}{section}{doc4}
\includepdf[pages=5-7]{document4}
\phantomsection
\addcontentsline{toc}{section}{doc5}
\includepdf[pages=8-]{document5}
\includepdf, but the overall technique is the same. – doncherry Sep 28 '12 at 21:49