I am learning guitar. I started about 8 months ago.
I did lessons at first, and they did help, but $100 a month is pretty steep. What I am currently doing (and wish I had done in the first place) is "Learn and Master Guitar". It's a 20 lesson DVD set with an instruction book. The DVDs are very well done and start at the very beginning. You start with parts of the guitar, how to fret, then do some simple scales and simple songs, then chords, etc. If you go through the series at the pace they recommend it is about 18 months total. The set sells for about $150.
http://www.learnandmasterguitar.com/
Each lesson has a basic lesson, tips and tricks (tuning the guitar, changing strings, etc) and then a workshop where he takes you through the practice part.
It honestly is very very well done and well worth the money.
I will probably pick up lessons again after I complete the series for the more advanced stuff.