Looking for a correct IPA transcription and a word-for-word translation of a song or aria? IPA Source provides all this for over 1350 poetic and 260 aria texts. Since this is a commercial site, there are fees for the services offered, ranging from $1.50 for an individual text or more for a full subscription. Here are a few free samples:
Botschaft--Daumer's text as set by Brahms
Vissi d'arte from Puccini's Tosca
A fascinating extra on the site is an explanation of the fach system, with explanations, representative arias, and sample recordings of the different voice types.