Below are the contact details and address for the Thai Embassy in Laos. Check regularly the Thailand visa process for Laos as their visa process changes all the time. At writing they will not issue multiple entry visas nor will they give anything short of a double entry Tourist visa when needed.
LAOS (Lao People’s Democratic Republic)
Royal Thai Embassy
Vientiane P.O.Box 128,
Tel : 214-582-3, 214-585-6
Fax : (66) 411-0017, (00785621) 214-580
Other Related Resources:
Thailand Visa Questions