I agree with most of the posts here. The hardest part of getting liquid is the nic content. The rest can be acquired easily.
It may be that zero nic juices can still be illegal or not. My opinion, don't tempt it. Might as well get the ingredients and mix it up.
And it's easier too as you'll only have to deal with percentage and no formula to dilute or lower nic levels.
There was a post above that links to one of the very first stores DIYers here started using. You can start from there.
USP grade PG might be hard to find locally but you can just use VG and Flavoring as a start. Get a handle of it first while looking for PG locally.
A lot of folks advised not to vape VG in its pure state and I agree. However, if you mix it up with a flavoring that's PG based and maybe a little distilled water, then you've got your mix. zero mg juice.
Hope that helps.