I'm looking online for a site where I can access a complete or nearly
complete collection of Charles Wesley's hymns *in Spanish*.  I've
found a few sites that present translations of five, ten, or twenty of
his hymns; but none that are any more complete than that.  Also, I
want them to be good translations that are metrical, that is,
singable, and that rhyme -- I do not want literal translations (such
as those found in Wesley's Works) that can't be easily put to hymn
music.  Thanks!

I'd be surprised if what you're looking for exists. Wesley wrote more
than 5,000 hymns.  Even most English-language collections are going to
have only a small portion of that, and I doubt that more than a few
dozen have been translated to Spanish in the way that you describe.

I suggest you contact the Wesley Heritage Foundation, which has
translated many of the works of John Wesley into Spanish and has also
translated many of Charles' hymns for the first time, and find out
what information it can provide.
http://www.wesleyheritagefoundation.org/

Thanks for the Wesley Heritage Foundation tip.  They have lots of good
stuff, and I did explore all the links there -- without finding what I
was looking for, unfortunately.  Most of the new translations of
Charles' hymns in Obras de Wesley are literal and not metric.  Of
course I don't really want all 5000 hymns in Spanish, but a hundred or
so would be nice.