'If you asked me now' or 'If you ask me now'? [closed]
You have heard both used because both are grammatical. Check out this page for an explanation of the different ways to phrase a conditional statement in English.
Consulting this page, in particular, the first example you list, "if you asked me now," is Type 2 Conditional, and the second, "if you ask me now" is either Type 0 or Type 1, depending on the rest of the sentence.