Guitar-makers come in all shapes and sizes: on one end, you have folks like C.F. Martin, the company that produces thousands and thousands of instruments every year. On the other hand, you have the one-person-shop luthiers, who might make but a dozen instruments in that time, plus or minus a few.
Martin makes fine guitars, but if you want a classsical guitar much better than entry level, you want to find a luthier who makes them by hand. The good ones -- and there are far too many for me to list here -- you'll have to wait a while until they can get to you. (There are some luthiers in their fifties who have stopped taking new orders because they worry they won't live long enough to finish the ones they have on order -- they might be ten or twelve years out.)
Among those who are outstanding makers, I will mention two: Alan Carruth and J.S. Bogdanovich. These men can make for you a concert-quality instrument at a reasonable price and in a relatively short time. There are links to them in my list on this page, and if you are looking for a fine classical guitar at a cost that won't require robbing a bank to pay it, please, go check them out. Neither man could make a bad instrument if they tried.
Both men are acknowledged experts in their field, though both would be quick to wave that off. Some people in the guitar realm -- me included -- have been trying to get Alan Carruth to write a book for years, and it is my hope that he does someday, because he is a wealth of information on the care and feeding of stringed instruments, and not just guitars. Talks the talks, walks the walk.
Jack Bogdanovich, who also can walk his talk, has written a book, just out: Classical Guitar Making: A Modern Approach to Traditional Design, and if you have any interest in the subject, this is a gotta-have-it book.
I'm a terrible craftsman, it's hard for me to figure out which end of a screwdriver to use, but with this book, I think maybe even I could figure out how to build a classical guitar.
The volume is chock full of pictures, detailed how-tos, drawings, and the hard-learned knowledge of years of practice. If you like guitars, you'll enjoying having this on your shelf. If you think you might want to build one, you can't pass it up. At $29.95, it is a steal, oversize format, more than 300 pp.
You can find Jack's book here