I bought some tobacco absolute flavor from Perfumers Apprentice, extremely high nicotine solution and pure PG from Xtreme Vaping....and Glycerin from Rite-Aid pharmacy. However, I have been too lazy to really play around with the stuff so can't really advise on DIY. Best to ask your questions in the DIY forum. That's where I got my information and they have some formulas for tobacco DIY (drop of this, drip of that sort of thing)
I have tried soaking a snu in a vodka/glycerin mix, but wasn't happy with the results....but mainly because the snu was lousy-tasting to begin with. Also tried soaking some raw loose tobacco in some PG. The nicotine won't really transfer, but the flavor will....and although it wasn't great, I likely could vape it in an emergency.