I married into the last name of Fornespierantoni and would like to
know who, when, where or how it originated from. I've tried
hyphenating it as Fornes-Pierantoni, but have had no luck. The only
search I do find is for Pierantoni, and its in Italian. Can you help
me with more information about this last name, in English?

Hello, what an interesting last name...if it were mine, I would want
to know all about it. I too turned up nothing when searching the name
"Fornespierantoni". It could have been - Piersantinio at one time.

However, using "Fournes" I came up with this: 
http://perso.club-internet.fr/vinny03/gene/bibal/index3.htm

Using "Pierantonio"
http://www.casa-longa.org/filiations/fg05/fg05_058.htm

Both of the above are names from France.

Here is an Italian sur-name group that has a website and newsletters,
all devoted to Italina sur-names. Perhaps you can find information
with this group!

More on Italian surnames:
http://www.arduini.net/names/names02.htm
http://www.angelfire.com/ok3/pearlsofwisdom/italynames.html

Good Luck

Berna,

I speak from personal knowledge here. Your name is awfully Spanish
sounding, of Catalan decent.  All names, Fornes Pier and Antoni are
very Catalan.  Given the Spanish tradition of taking your father's
last name, followed by your mothers, and then following your husbands,
I would venture to guess that this name is a combination of all these
three.  Whomever gave it to you somewhere down the line put them all
together and it remained that way.

I hope this helps,
Claudietta