I have heard the diagrams done by Mark Lemmon are most accurate. I think they can be found on the web and also published in his book
link
I think he did a huge mural for a place called the "Alamo Beer Brewery" in san Antonio. I do not know if it is still there:
"Lemon, who has done numerous works on the famed siege and battle, including one that hangs at the Emily Morgan Hotel, spent 3,500 hours over 14 months and $1,500 USD of his own money to paint the 8-by-15-foot work in his garage in Georgia, even though the work was not commissioned. The painting, up for sale in the "six-figure range," will be displayed for two years at Alamo Beer, which will hold public grand opening events Friday through Sunday at its near East Side location next to the Hays Street Bridge.."
You can see images of the mural here
link
I have a very detailed diagram in the Osprey "The alamo 1836". There are several 2 page layouts of the entire compound.
I also have a softback booklet from the Alamo, named "The Alamo Long Barrack Museum". Compiled by the Daughters of the Republic of Texas. On page 26, there is a complete compound diagram done by Mike Waters, dated 10/7/85. It is very close to the Osprey diagram. One significant difference is the stockade that was manned by Crockett. The Osprey has 1 cannon at the stockade, the booklet has 3 (maybe 4) cannon. So not sure which is more accurate. It seems every version someone does of the compound is different than any other version already in existence.