In most lists of irregular verbs in particular the list in my Langenscheidt's dictionary, the list contains the infinitive, the past tense, and the past participle forms to show the irregularity. However it doesn't list the irregularity in the conjugation in the present tense (for example for lesen there is no indication that the stem changes to lies in the second and third person singular). And the irregular conjugations aren't listed in the entry for the word (such as lesen) or as seperate entries (liest). Is there some way that I should be able to know the present tense changes from the past and past participle changes? Or do I need to rely on a different source to learn the present tense conjugations of irregular verbs?
Probably an older edition. Normally lists of irregular verbs are not the state-of-art. And in older editions such lists were meant mainly for Germans. Gradually publishing houses have discovered that there are people who want to learn German and that dictionaries for learners require a totally new concept.
Have a look at recent editions of dictionaries, Langenscheidt or Pons, and you will see the difference.