iTunesJoin is a set of applications that lives in the scripts menu of iTunes and allows you to join (concatenate) multiple tracks into a single new track.

You can:
-Join AAC audio tracks into a new AAC audio file without quality loss;
-Join any tracks (except protected AAC) and convert the joined file according to iTunes import preferences.
-Join any tracks (including protected AAC) into a QuickTime movie (without quality loss) that can be played by iTunes (but, unfortunately, not by iPod);
-With the optional ChapterTool software from Apple, automatically create chapters for easy navigation (iTunes 4.9 and above; AAC files only).

New in this version:
-Fixed crash when joining enhanced podcasts with pictures
-Name files better for users with “Keep iTunes Music Folder organized” unselected.

Important news for current and former iTunes 5 users. iTunes 5 has several bugs that affect iTunesJoin. Although iTunesJoin is able to work around all the known bugs in iTunes 5, we recommend that you either revert to iTunes 4.x or upgrade to iTunes 6; you should also reimport any tracks you imported with iTunes 5. Tracks joined with iTunesJoin using other versions of iTunes may not work under iTunes 5. If you must use iTunes 5, you will need to re-join those tracks or use the "Fix iTunesJoin Tracks" script from iTunesJoin 1.1 (available at author's site).

Limitations: If you use any of the files you produce with it, you are required to purchase a license. It will function for 30 days after it is first used; an additional 10 day trial can be initiated any time after the first trial period expires. Upon expiration of the second trial, you will need to purchase a license to restore functionality.
You can purchase a license for US$10 per seat. Multiple computer households need only purchase a single license, so long as this is for personal use only. Site-licenses for non-personal uses are available.

Requirements:
-OS X 10.3.9 or later
-QuickTime 7.0 or later

Universal Binary