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 4m 41s ago
Delete characters from the beginning or ending of selected tracks' name, artist, album, comments, composer, or show tags
downloaded 31m 56s ago
Recreate a playlist such that its visible columns mirror the Music library
downloaded 33m 35s ago
View/Edit tags of selected track(s) in single window
downloaded 35m 29s ago
Remove iTunes tracks disassociated from files
downloaded 1h 22m 35s ago
Batch set new Last Played/Last Skipped of selected tracks
downloaded 1h 50m 21s ago
Perform search-and-replace on text in your choice of tags