In the Qur’an, ‘Ad and Thamud are always mentioned together. Moreover, the verses advise Thamud to take warning from the destruction of ‘Ad.
To the Thamud people (We sent) Salih, one of their own brethren: He said: “O my people! worship Allah: ye have no other God but Him” “And remember how He made you inheritors after the ‘Ad people and gave you habitations in the land: ye build for yourselves palaces and castles in (open) plains, and carve out homes in the mountains; so bring to remembrance the benefits (ye have received) from Allah, and refrain from evil and mischief on the earth.
image links;
http://upload.wikimedia.org/wikipedia/commons/4/45/Thamudi.jpg
http://i256.photobucket.com/albums/hh162/speed2kx/Thamudi.jpg
From the Sealed Nectar (Raheeq al Makhtoom) by Mubarakpuri:
“Do not enter the houses of those who erred themselves lest what had happened to them would afflict you, but if you had to do such a thing let it be associated with weeping.”
Then he raised his head up and accelerated his strides till he passed the valley out.” [Sahih Al-Bukhari 2/637]
http://www.witness-pioneer.org/vil/Books/SM_tsn/ch7s3.html#The%20Muslim%20Army%20is%20leaving%20for%20Tabuk
More pictures and information on the people Thamud:
http://www.zubeyr-kureemun.com/SaudiArabia/MadainSaleh.htm
http://www.iqrasense.com/islamic-history/madain-saleh-cities-inhabited-by-the-people-of-thamud.html
http://en.wikipedia.org/wiki/Thamud
Or simply do a search on Thamud.