This is where our community discusses almost anything! While we're mainly a Cambodia expat discussion forum and talk about expat life here, we debate about almost everything. Even if you're a tourist passing through Southeast Asia and want to connect with expatriates living and working in Cambodia, this is the first section of our site that you should check out. Our members start their own discussions or post links to other blogs and/or news articles they find interesting and want to chat about. So join in the fun and start new topics, or feel free to comment on anything our community members have already started! We also have some Khmer members here as well, but English is the main language used on CEO. You're welcome to have a look around, and if you decide you want to participate, you can become a part our international expat community by signing up for a free account.
Look for other regions names for corn meal (I think corn meal is the American term), I know that in NZ/Oz it is usually called corn/maize polenta. Corn flour is the starch derivitave which is generally used as a thickening agent.
A quick google search should give you a list of different names for it, and then check out the supermarkets, I am sure you will be able to find it somewhere, sorry I cannot be more specific.