You can find the archiver library from the web sites below.

SharpZipLib - http://www.icsharpcode.net/OpenSource/SharpZipLib/
Sqx Archiver - http://www.sqx-archiver.org/
XacRett - http://hp.vector.co.jp/authors/VA030681/App/XacRett.htm
Unlha - http://www.csdinc.co.jp/archiver/lib/unlha32.html
Unarj - http://www.csdinc.co.jp/archiver/lib/unarj32.html
7-zip - http://www.csdinc.co.jp/archiver/lib/7-zip32.html