Hi Jason,
You will want to copy the template named 'toc.line' from html/autotoc.xsl to your customization layer and modify it to add author. This line of XSL generates the title:
<xsl:apply-templates select="." mode="titleabbrev.markup"/>
The context node for that template is the element for that line in a TOC (chapter, section, etc.). So you would want to add an xsl:if statement after the title to include the author, something like this for DocBook 5 (remove the d: namespace prefix if DocBook 4):
<xsl:if test="(self::d:chapter or self::d:article) and d:info/d:author">
<xsl:text> </xsl:text>
<xsl:variable name="author">
<xsl:apply-templates select="d:info/d:author[1]" mode="titlepage.mode"/>
</xsl:variable>
<xsl:value-of select="$author"/>
</xsl:if>
The $author variable is used to strip any formatting that would be applied by titlepage.mode using xsl:value-of, which returns only text.
You can add a CSS selector matching on class 'tocauthor' to format the author name in the TOC.
Bob Stayton
Sagehill Enterprises
bobs@sagehill.net