By first-hand experience and also by this other SO answer, usually IISExpress holds a directory with its own data files at: C:\Users\<username>\Documents\IISExpress
.
There you can find the default directories for each web site log files (Logs\
and TraceLogFiles\
) and especially you can find all web sites configurations in file config\applicationhost.config
. That one has a <sites>
section with a <site>
node for each website created.
For each website, its <virtualDirectory>
node specifies actual root location in physicalPath
attribute:
<site name="YourWebSiteName" id="12345">
<application path="/" applicationPool="Clr4IntegratedAppPool">
<virtualDirectory path="/" physicalPath="D:\Physical\path\to\your\website\root"/>
</application>
...
</site>