Are there any places I can obtain free printed maps of SEA or countries within? I'm travelling from San Francisco, USA and am going to Thailand and Bali, Indonesia. Feel free to extend this question to any country or region. Generally, do visitor centers offer them? Do consulates or embassies? Airports?
Very, very often, as you arrive at the airport of a country you'll see free (or cheap) maps for tourists. They'll often highlight key accommodation spots, or restaurants or tourist sites. These are (more often than not) immediately after you exit to land-side - ie where friends/relatives wait for you. There's often an information counter or desk with brochures, pamphlet and maps. If you don't know the language, look for the 'i' (often indicating information) or ask a member of staff. If you're flying into Bangkok, there will be maps around the area where you can pick up the taxis. There will be maps which have the MRT, SkyTrain, ect as well as Bangkok. They're at the airport information desk.
In addition, if staying in a hotel or hostel, they'll usually be able to provide you with one as well.
Failing that, information centers in the town, car rental companies, tour operators (eg find a walking tour company, they often have free maps that show you where their tours go) and even libraries may be able to help.
If you want to explore the surroundings, Soviet-era topographic maps are not only free, they're often the best topographic map available, usually at a scale of 1:200.000, often better. They're not optimal as city maps, and for city maps there are probably better sources available anyway. They're also quite dated, usually from the 1980s or older — a friend used them to walk from France to Mongolia, and at one point they suddenly came upon a large hydro power lake that wasn't on their map, so they had to make quite a big detour.
You will need to read the Cyrillic script.
The answers to my question over at GIS describe sources where these maps can be downloaded.
In general, try asking at the countries' national tourist offices, for example - the one in San Francisco.