Heck, just use Toast to make Disc Images out of them, though as I recall Toast only supports FLAC, not APE. You'll need xACT to convert the APE files into AIFF. You can then mount the disc images using Toast (either by using Utilities > Mount Disc Image in Toast itself, or by using the contextual-menu option "Mount It" right below "Toast It" in the Finder) and rip from iTunes as though they were a regular CD. It'll even go out and get CDDB info just like putting in any other physical CD.