To locate your UPC and ISRC codes, navigate to Distribute ► Releases. From here, you can either search the release title or scroll to the release and click on it.
On the Release Details tab, you'll find the UPC for your release.
To find the ISRC codes, scroll down a little further to the tracks section.
If you're looking for a full list of your catalog metadata (UPCs, ISRCs, Release titles, Track titles, etc.), you can export your catalog inventory by selecting Export Inventory under Distribute ► Releases.