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 7m 27s ago
Exports and then re-imports selected tracks' artwork
downloaded 11m 14s ago
Remove iTunes tracks disassociated from files
downloaded 14m 19s ago
Swap the name with the artist of selected tracks
downloaded 15m 11s ago
View/Edit tags of selected track(s) in single window
downloaded 41m 41s ago
Batch-create music playlists by indivdual year
downloaded 1h 9m 33s ago
Displays Rating in a Notification as tracks play