one of the best place was Spokyz but he closed his WWW access due to lot of abuse.
You can find lot of Codetapper WHDLoad install games at http://zap.to/action
few at Bored Seal Page : http://bored.webzdarma.cz/Index-Amiga.html
Jean-François Fabre page : http://jffabre.free.fr/amiga/patches.html
and check links on each page and don't forget to check http://www.whdload.de