Today I had pictures from the US trip printed in Zeer Rangsit. The quality was only decent, but for a 1-hour-photo and 4 Baht for a 4″ x 6″, it is still good value. Problem is, it still requires 2 trips to Zeer, which I had to do during lunch break. So I did a quick search for photolabs which will let me upload my files and mail the prints back.
First hit was Print@Kodak, which I have used a few times while in Singapore. For 4″ x 6″, they charge 5 Baht/pic plus delivery, with 2-day turn around time. Another one I found is ThaiQuickPix, which looks cheap (usually not good when photography related) and is cheaper than Print@Kodak for larger prints. Verdict: Kodak for the time being.