Phone screen type questions might be stuff like fibonacci, find the min in an array, or find the intersection (shared duplicates) of two arrays.

In-person stuff varies: some companies ask me more practical/specific stuff like Ruby/CSS/JS implementation/coding/design/architectural questions. Others ask puzzle type questions that require me to use data structures in clever ways. Interestingly, hashes and trees are my go-to data structures. Do depth-first search and breadth-first search and that'll get you pretty far with trees. 90% of questions I'm asked require using hashes and/or trees in clever ways.

I actually find interviewing gets more and more fun as you get into it.