20-30% VG, which gives the vapor, is pretty standard and what I use in my DIY liquids. You're welcome to do a higher % or even all VG, but the PG helps create the "throat hit". You will need to dilute the
juice with alcohol or distilled water more as you use more VG.
It will depend on your area for if you can get PG locally, I ordered it online with some unflavored
juice from myfreedomsmokes.
VG can be found at wal-mart in the first aid area, hobby stores, and in some health and beauty places with the lotions.
The DIY
juice websites would sell both and flavorings. Haven't ordered anywhere, so I can't make a recommendation.