One good book you should buy, is the "Lonely Planet" for Bolivia. It´s the most complete - although not always accurate - collection of informations about Bolivia. I use it a lot because it gives you always some good ideas.
Safety: I would be careful with expensive photography equipment because pilferage has risen a lot in Bolivia. The "El Alto" area around the airport is basically safe, but if they see you loitering with nice equipment, you are an easy prey, and I would not really recommend hanging around alone with costly materials as you can be an easy prey. Since the El Alto area has a high crime rate (one of the highest in Bolivia), plus a low income rate, and last-not least, not very reliable police protection, you might steer clear from adventuring around alone.
Don´t be frightened. You will not get mugged first hand! It´s just like in all major cities. If you show off what you have and others don´t, you are a prey. That can be in Sao Paulo, Milano, London or El Alto.
I never heard of police prohibiting photography at the airports. If they do approach you, they will probably just be looking for some bribes.
Next: Hotels: In El Alto they have plenty of so-called Alojamientos. But I would steer clear from them and go down to the city (20-30 minutes of very interesting drive), and take any of the 2-3-4-5 star hotels they have there. It´s safer, more comfortable and specially at night, you can still walk around, which in El Alto, you cannot do.
Aviation: If you want to fly a perfect condition DC3, then you can take flights from LPB/CBB, to very, very interesting flight destinations like the Salar de Uyuni (enormous salt lake), or to Rurrenabaque (flight "between" the Andes towards the tropics). The aircraft is owned and flown by the Canedo family (Lineas Aereas Canedo = have nothing at all to do with Vasp), and have their base in Cochabamba. They are operated on behalf of Aero Sur http://www.aerosur.com/
You can contact and see informations of Lineas Aereas Canedo under http://www.lineasaereascanedo.com/. They used to have also Convairs in perfect conditions, they were sold however, to Rhodos Air in South Africa.
Their DC-3 is really in good conditions as I heard.
If you want some nice flights with 727's, take LPB to CBB or VVI, they take you very close to the Illimani, a breathtaking sight if you have good weather. Make sure you take day-flights
And if you fly into LPB from LIM
, chances you will get a 721 are quite good, and the flight is really great, overflying the Lake Titicaca on one side and the snow caped Andes on the other side.
The chances to catch 721's are quite good for inland flights, but I would not rely too much on infos of www.amadeus.net when they "offer" the 721, because LB
switch quickly the aircraft according to demand. And this can be from one minute to the other.
I know, that there are C46's flying mainly out of LPB, but I really don´t know the actual operators, nor if the aircraft are safe enough to fly on.
If you want to fly some vintage F27's then you should take a TAM flight within Bolivia (has nothing to do with TAM Brazil). They are the military "civil" transport which reach remote areas of Bolvia.
For a more modern and highly demanded prop route, take http://www.emarketing.com.bo/amaszonas/
They fly Cessna Caravan to some nice destinations and target to foreign tourists.
For best spotting, I think VVI and SRZ give you the best options (VVI for international and national flights, mainly jets, SRZ for mainly regional flights and military flights, mainly props/vintage props).
As for cheap flights: Maybe you can think of a vibolpass of LAB (www.labairlines.com.bo), which takes you for USD 250.- up to four cities. It´s a good deal, and cannot be purchased in Bolivia.
And if you want to go to an airport terrace (protected by hexagonal mesh), then CBB is your destination.
SRE/TJA/TDD have such low traffic that they should not be of much interst, although as cities, they are lovely.
Any other questions?