Who gives study classes for an TACL license ?

I will assume you are in Texas and you are talking about the Air Conditioning and Refrig license? But the letters also refer to a Tanning license. So you need to be clear what you are referring to.

Can't personal recommend this web stie but:
What Does it Take to Earn a HVAC License or Certification? (http://degreedirectory.org/articles/What_Does_it_Take_to_Earn_a_HVAC_License_or_Certif ication.html)

Also most of your local tech schools should have classes