30 day visas can be obtained on arrival at most entry points into Laos. In most cases it is cheaper and easier to get the visa at the border than at an embassy or consulate.
At the more out of the way entry points you may have to wait some time while immigration issues a visa.
You will need the following:
Passport sized photograph
Visa fee of $US35
Visas can easily be extended twice for a service fee of US$3 plus US$2 per day. It is cheaper to just go across the border and come back and get a new visa.
Visas are available at all International Airports and all major border crossings.
Visas are required to be organised in advance for visitors holding passports from Afghanistan, Algeria, Bangladesh, Burundi, Cameroon, Congo, Cote d'Ivoire, Ghana, Guinea, Guinea Bissau, Jordan, Lesotho, Liberia, Libya, Mozambique, Nauru, Niger, Nigeria, Pakistan, Senegal, Sierra Leone, Sri Lanka, Suriname, Syria, Swaziland, Tonga, Turkey, Zambia are Zimbabwe.