About practicing
Hi David!
One question, how would you organize your practicing, assuming you had 8 hours per day to practice?
Can you get a little bit specific?
That's great that you have some prior training on another instrument. I recommend you continue your guitar work... practice it at least 30m a day. You are valuable to a band knowing how to play two instruments. You can also PLAY what you're looking for in a song instead of talking about it.
It is a good idea to keep practicing until you can get the technique down, so you'e on the right track. The great thing about this is that when you get that one technique down, it's mastered for when it comes up again. You do not need to do one hour per area... it's up to you how you spend your time. Simply put, when you have the harmonica in your mouth, you're learning. You don't want to neglect those other areas of discipline though. For example, if you're a good soloist, from studying songs and such, but don't know how to play accompaniment well, that's a real hole in your playing.
I know you're really serious about this, so I'll take some more time and go deeper for you. Assuming I was where you're at right now, this is how I would structure my practice day...
1) 15m - Warm up playing scales: Major Pentatonic and Blues Scale for each chord of the three positions (C, G, D, A) across the entire range of the harmonica.
2) 15m - Arpeggios: Major, Minor and 7th Chords from of all the chords based on the home scale in three positions (C, G and D scales)
3) 60m - Study Song (do all the songs from BluesHarmonica.com first, then songs from artists)
4) 30m - Take a lick from the song I'm studying and apply the Chorus Forms process for improvising with it (see Improvising Study 1)
5) 30m - Music Theory: As it pertains to the harmonica... like hole changes for example (Accompaniment Studies 3 and 5)... and learning how to play killer V-IV-I's (Improvising Study 4) and Turnarounds (Study 5), and then I-vi-ii-V-I progressions (Music Theory Study 6), using a program like iReal for example to work on it in motion.
6) 30m - Accompaniment Playing (from studies on the site and/or copying what someone else did on recording and/or playing to songs in my collection that have no harp to mimic real-life playing... again, make sure to finish all your Accompaniment studies on the site first)
7) 60m - Study Song (continued work)
8) 30m - Solo Harmonica Study (chording, chugging, etc., anything that has me playing unaccompanied)
9) 30m - iReal Practice - Grab a random song from iReal and practice playing to it... this helps me to apply my scales, arpeggios and music theory knowledge.
10) 60m - Guitar practice
11) 30m - Standards: Learning the songs that are most likely to be called at a jam session or gig
12) 60m - Study Song (continued work)
13) 30m - Apply Chorus Forms process
Notice a consistant theme... master the material on a given subject from the site first. No need to reinvent the wheel. I had to figure this out on my own... 10's of thousands of hours of work... you can benefit from this. After mastering what I present for you, move on to other artists and learn their approach and vocabulary (technique won't be an issue, you would have already learned it from the site). Best wishes on your journey!
Eight hours a day, that will get the job done. I recommend you follow the Levels of Achievement outline, which already includes the important areas of study... technique, movement and vocabulary (via study songs); solo harmonica playing (self-accompanied); accompaniment playing; improvising and music theory.
In addition to this I recommend you do rhythm training and ear training (there are computer programs out there for this) and spend time learning a harmony instrument, most commonly piano, but in the blues world guitar gets equal billing, so that would be fine as well.
Make sure to give yourself breaks, say 5m for every 20m of study... our brains process better this way.