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 52s ago
Gather audio tracks whose files contain no artwork metadata
downloaded 3m 36s ago
Exports and then re-imports selected tracks' artwork
downloaded 6m 33s ago
View/Edit tags of selected track(s) in single window
downloaded 8m 22s ago
Export album artwork as folder.jpg to Album folder
downloaded 21m 26s ago
Export artwork of selected tracks to parent or specified folder
downloaded 25m 24s ago
Applet assists with swapping, copying, appending data between track tags