After giving up on trying to learn the characters when I was casually learning Chinese, I thought Thai would be a relief because it has an alphabet. In theory, yes - but here are some of the difficulties I've been dealing with.
First of all, there are 44 consonants (which all have a two-word name /and/ associated thing you have to learn, similar to "a is for apple") and 32 vowels (long and short). The consonants are divided into high, low and middle classes which help to determine the tone of the syllable. The vowel is placed before, after, above, below, or on both sides of the consonant depending on the vowel. One of the consonants is a vowel and some of the vowels have consonants in them.
Sometimes letters exist in a word only to help it become a certain tone and are not actually pronounced. There are high, low, rising and falling tone markers (mid doesn't have a marker) which are placed above the syllable, but contrary to what you might think (and what would make sense), a low tone marker doesn't actually make the syllable a low tone, nor does the consonant being in the low class cause it to be low tone. There is a maddeningly complex system of interactions that determines the tone of each syllable, many of which I still do not understand. Some sounds have several possible letters, for example there are 6 letters that represent aspirated 't,' and depending which one you use, it changes the meaning of the word. Did I mention there are no spaces between words?
I am enjoying learning however, and I drive around looking at license plates and saying the letters to myself (signs are still too complicated). Also, I'm sure my hard work will pay off because once I can read, it will be so much easier to learn to speak (which is also coming along slowly but surely)!
My super-awesome linguist Thai tutor bought this cute book for me (the same one Thai kids use in Kindergarten)