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 14m 25s ago
Exports and then re-imports selected tracks' artwork
downloaded 37m 33s ago
Copy files of tracks to selected folder
downloaded 44m 52s ago
Use tag data to formulate new file name for selected tracks' files
downloaded 1h 29m 34s ago
Perform search-and-replace on text in your choice of tags
downloaded 1h 50m 36s ago
Batch-change the Album Rating for the albums of selected tracks
downloaded 2h 57m 16s ago
Copy chosen tag info from one set of tracks to a different set of tracks