There is a bus from Kunming going directly to Vientiane for about US 50$ and the Lao visa will cost you 30$ to enter the country.

I'm very sure you can only get a 30 days tourist visa and later on extend it in China for another 30 days unless you have an invitation of a school or company that is offering you a different type of visa.

You could go to Vientiane in Laos. Very relaxed place. Not much to do than just visit some temples and go to sleep early at night. When you are there you could go to Luang Prabang in Laos. Very relaxed atmosphere. I'm not sure if they issue 90 days tourist visas. Probably 30 days. I'm not sure my friend.

I'm a Belgian passport holder. Last year in September 2009 I was issued a 30 days Chinese tourist visa in Bangkok. I went to the Chinese Immigration Office in Nanjing (can be found in any major city in China) and they gave me a 1 month extension. You can get only 1 extension and then you have to leave the country and apply for a new tourist visa. I'm sure you can extend your tourist visa in Kunming.