Are there any decent pay as you go plans etc that I could use on my phone while travelling through Vietnam, Cambodia, Thailand and Malaysia?
Would primarily use it for texts, emails and the odd call home.
Already have a phone I could use just not sure what is available for this. Any pointers appreciated.
Yes, you will be able to find prepaid plans with data. You will find a list of service providers here:
The last time I was in Thailand, the people at the hostel told me to get a DTAC prepaid SIM.