Anglo Incognito

I am in a panic. I was asked to sing for a large Hispanic convocation in January at our church and I agreed to do it. I wanted to make my husband proud that I can fit into his world. And now I'm wishing I never said I'd do this.
There are few songs in Spanish that I can find, that are in the classics category required by the minister of music. I can't figure out how to search for Spanish titles that I don't even know, or where to do that.

My father in-law has sung for years at his Spanish church. Just this year he gave all of his music to someone else--all that richness and history--in several boxes. So all he could send me was "O Sole Mio" in Spanish. He said I'd need to change the words a little bit to give them sacred meaning, but he didn't give me any idea of how to do that.

I turned to my minister of music friend, Bobby. He reassured me that yes, he had music in Spanish, and in fact, had just received a number of pieces that he thought would be good for Cinco de Mayo weekend. Bobby graduated from Princeton, and has excellent musical taste. Knowing that he was working on this for me was very comforting.
Yesterday the music came in the mail. I proudly carried it to the piano and started playing and singing through it. Sam sat nearby at his computer browsing for something or another. The introduction to the first song sounded like the accompaniament for "La Cucaracha." Sam turned toward me in his chair as I began to sing loudly en Espanol. As the last note of the first verse ended, Sam cleared his throat. "What is that?"
"Beats me. But it's in Spanish. Did you understand what I was saying?"
Sam looked dubious. "Kind of. But the words are really wierd. I hope you aren't planning to sing that."
Deflated, I sang through a couple more of Bobby's choice songs. Another one had a mariachi-type sound and I sang with gusto. It made me feel like Carmen Miranda. Sam turned back to the computer shaking his head. "You're going to have to find something else. These songs are awful." I am now the owner of six awful songs in Spanish.

I think I have finally found something. I took my Spanish hymnal and found words with the right meter to superimpose on the English tune, "O Waly Waly." It's a beautiful tune, and the lyrics are majestic and wonderful ("O For a Thousand Tongues to Sing My Great Redeemer's Praise").
Sam informed me that there will be lots of evangelistic "big guns" in the Hispanic community who will attend the January convocation. I'm singing through my song every day now, so I don't sound like an Italian wetback up there. Just call me the Anglo Incognito.