Most flavorings will be in PG solutions. There are a few brands that use alcohol. I've seen very few flavorings that are in VG. Often, a typical flavoring may have a combination of PG and alcohol (and sometimes water.)
If you don't have any serious aversion to PG, I'd recommend Wizard Labs for their overall excellence as a DIY vendor, though I have other vendors that I like to buy from as well. I'm sensitive to PG, but 20% or less in a mix does not bother me, so I use their flavorings. Note that they list the ingredients and the manufacturer on each flavoring page.
I don't use e-juice calculators, but ejuicemeup is popular, still maintained, and made by an innovator in this community. Can't say much else about it, other than I think it has lots of recipes included, too.
EcigExpress has lots of flavorings, as well. You can also buy directly from some manufacturers, like the Perfumers Apprentice.