Sure, iTunes can join tracks, but only if they're consecutive CD tracks, and you haven't imported them. This script allows you to join any two (or more) MP3 tracks (repeat: MP3 tracks only), provided that they are the same format and bitrate.
Also see Join Together, an application that will join any type of files.
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downloaded 35s ago
Set the Plays of selected tracks.
downloaded 1m 25s ago
Batch set new Last Played/Last Skipped of selected tracks
downloaded 2m 13s ago
Copy chosen tag info from one set of tracks to a different set of tracks
downloaded 2m 52s ago
Perform search-and-replace on text in your choice of tags
downloaded 4m 14s ago
Delete characters from the beginning or ending of selected tracks' name, artist, album, comments, composer, or show tags
downloaded 5m 19s ago
Renumber order of selected tracks