As mentioned, there is the AOPA guide or the country airstrip guide (by state), both of which are sold in pilot shops. I get the impression you may be referring to your school's ALA register, in which case there will be a collection of unlicensed/uncertified strips (ALA's) that are allowed to be used for training flights.
Generally, the schools Operations Manual will prohibit flights into airstrips that haven't been verified and entered into this document.
