La Paz - Rurre / Rurrenabaque: TAM - Transporte Aéreo Militar - has a flight five days a week. Línea Aérea Amaszonas has four or five flights a day. TAM uses a Xian MA60, a Chinese airplane with 56 passenger seats, while Amaszonas uses a Fairchild with 19 seats.
Amaszonas ("A más zonas" = "to more zones"), Aerocon (Línea Aérea Bandera del Beni) and AeroSur ("La Aerolínea de los Bolivianos") co-operate.
The website of TAM is www.tam.bo</a>. This site has not worked for months, but today it is online.
(TAM should not be mixed up with the Brazilian owned TAM Group of airlines).
Once a week, on Tuesdays, TAM fly Trinidad - Rurrenabaque - San Borja - Trinidad with a CASA C-212-100.
Three days a week Amaszonas fly Trinidad - San Borja - Rurrenabaque. See the thread Santa Cruz to Rurrenabaque?, 29-Mar-2010.
About LAB (Lloyd Aéreo Boliviano) and a "replacement":
Boliviana de Aviación is a new airline with a name similar to Cubana de Aviación.
About the airstrip / airfield ("airport") of Rurrenabaque: It is expected that the runway will be paved here in 2010, cf. reply # 7 in the thread First timer: Bolivian Busses, 11-Mar-2010.
In general to find information about flying: Use the encyclopedia Wikipedia at en.wikipedia.org. All airlines and many airports in Bolivia are described:
Category: Airlines of Bolivia and Category: Airports in Bolivia
A useful page about airlines and airports in Bolivia: Boliviabella.com/airlines.html
About tours from Rurre / Rurrenabaque I can refer to reply # 3 in the TT thread Some questions for our Bolivia experts, 07-Mar-2010.
About posting here at TT: Apparently you have posted your question in the general South America branch. If / when you ask about Bolivia again, I suggest that you post direct in the Bolivia forum. A thread in the Bolivia forum also appears in the general South America branch.