Troubleshooting SharePoint typically involves reviewing the trace/ULS logs. These logs will reference web applications, site collections and databases by their ID or guid. No obvious GUI exists to pair these objects with their id. Administrative boundaries may prevent accessing the SQL server administration utilities which can also be used to do this
Through the Sharepoint Central Administration utility we can reveal the ID's of these objects in the following ways
Web Application ID
Browse to Central Administration. In the Application Management tab select Content Databases. Change context to a second web application other than the one initially displayed when you first come into Managing Content Databases using the drop in the upper right. If the desired web application was initially shown in Managing Content Databases, select another Web application from the dialog other than the current, then repeat changing back to the disired web application. Otherwise select the desired web application. The web application id will be in the address bar of your browser as in the following.
http://moss.contoso.com:2345/_admin/CNTDBADM.aspx?WebApplicationID=<id of the web application in guid format>
Content Database ID
Browse to Central Administration. In the Application Management tab select Content Databases. Change context to the web application with the database you want to look at if not seen when initially coming into Manage Content Databases. Doubleclick on the database name of the desired database in the database name column. The database ID will be in the the address bar of your browser as in the following.
http://moss.contoso.com:2345/_admin/oldcntdb.aspx?DatabaseId=<databaseid with %7B as a leading space and $2D as a hyphen>
Site Collection ID
Browse to Central Administration. In the Application Management tab select Site Collection Quotas and Locks. Change context to a second site collection other than the one initially displayed when you first come into Site Collection Quotas and Locks using the Site Collection drop down. If the desired site collection was initially shown in Site Collection Quotas and Locks, select another site collection from the dialog other than the current, then repeat changing back to the desired site collection. Otherwise select the desired site collection. The site collection ID will be displayed in the address bar of the browser as in the following
http://moss.contoso.com:2345/_admin/delsite.aspx?SiteId=<id of the site collection in web format>
DatabaseID SiteID WebID