A Thai tutor is an excellent choice for learning how to speak Thai. In Thailand, the language is expressed as a second language, so the students will learn a bit of the primary language first and then progress to the next level. There are also some private schools which have excellent Thai teachers. Private schools are also able to cater to different groups.
The other option is to go to a Thailand expatriate who is willing to teach you how to speak Thai. They will teach you at your own pace and within limits. The expatriate can be very informative, but he might not answer all the questions you may ask. He will, however, give you enough time to finish a lesson.
You should be able to speak Thai in Thailand if you want to communicate with people in Thailand.