This is the quickest way to put different icons for downloadable files, via CSS, no JS or PHP needed.
[css]
a.download-link:before{
content: url('default.gif');
margin-right: 6px;
vertical-align: middle;
}
a.download-link[href$='.pdf']:before{
content: url('pdf.gif');
}
a.download-link[href$='.doc']:before,
a.download-link[href$='.rtf']:before,
a.download-link[href$='.txt']:before {
content: url('doc.gif');
}
a.download-link[href$='.docx']:before {
content: url('docx.gif');
}
a.download-link[href$='.xls']:before {
content: url('xls.gif');
}
a.download-link[href$='.xlsx']:before {
content: url('xlsx.gif');
}
[/css]