For guitar songs that typically require a Capo, is it possible to play the song without one??

Usually. The other thing you can do though is transpose it.

Yeah, but it creates quite a bit of hassle with going from open chords to barre chords and back again. Just put on the capo, then transpose from there.

even if you can play without a caop, songs that are written and played with a capo sound better if you use one at least to me - because of the voicings, and the way certain strings sound "open" with the capo on

I ask because sometimes i'm trying to transcribe a song by ear, and after spending an hour or so i'll get frustrated and look at the tabs, and see that there is a capo involved.

if the song's all chords, here's how you should go about transcribing
first find the root note and finger the major/minor chord depending on the song
then add in or take off individual notes in that chord (suspends, adds, etc.)

if it's a solo, it shouldn't matter if the capo is there or not