Many people have said it, I will as well, the Alamo is a little underwhelming. Only a small portion is left of the original large compound. Also, no pictures are allowed so I only have a few to share.
Ten years ago I visited this museum but was not allowed to take pictures then. They now allow pictures, below. It is a powerful museum and I hope you can visit. I also visited the Old Capitol Building where Lincoln argued cases before the State Supreme Court and where he sat while a State Representative.