Barre chords? Go to a pawn shop and buy a used bottom-end imported-from-God-knows-where Fender Stratocaster (or clone thereof) for about $100 USD. Practice barre chords on it. A Strat has extra-light action and a remarkably comfortable neck profile. It's made for playing barre chords. Don't worry that the thing sounds like crap; it's a learning tool, not a musical instrument. Once you've gotten comfortable with playing barre chords on the Strat, transferring the skill to an acoustic is just a matter of learning to apply a bit more pressure to the strings.