The only thing I can make out on your label is that the guitar was built by a Ferrer. This is a very distinguished family of guitar builders in Granada going back at least 4 generations. I'm not sure which family member built your guitar since "A" is the only letter on the label. Your guitar appears old so I'm not sure who the A is referring to. At any rate, this could be a valued instrument
I suggest you get in touch with a classical guitar dealer, they can probably easily identify your guitar and give you a value estimate.
I've never corresponded with this dealer, but they appear to be well versed in Spanish instruments. They also have a "sell your guitar" button on the left side menu on their site. See if they will reply to an email.
Here is a short bio on Eduardo Ferrer, a contemporary family member:
Jedistar also has a little information on the old man Eduardo on his site, just scroll down:
Statistics: Posted by VintAxe — Mon Jun 14, 2010 8:44 pm
]]>