I wouldn't worry about getting everything from one place. The heavy stuff that would cost a lot to ship can be ordered in bulk (nic, VG, PG - like 1-2 years'+ worth), and if you do, you can go for the quality you want and save a ton of money while you're doing it. Plus, if your state gets funky like AR, you'd be set for awhile. You can get nic highly concentrated (like 60-100mg), so even 250ml can last you a really long time, and shouldn't cost very much to ship. When bargain hunting for nic though, keep in mind that some brands will affect your flavors and you'll be stuck with that for awhile, so may be wise to go for quality. Nude Nic and VaporTek are the two I've been hearing good things about lately. Essential Depot regularly has crazy deals with free shipping on really good VG & PG by the gallon, and a lot of people here will attest to the quality/purity of their product.
Get those out of the way and you'll be down to flavoring - tiny bottles, plenty of places ship USPS first class, so no big deal. Murphy's Law applies: no one store will have ALL of the flavors you need - but their prices are pretty comparable, so find one that has most of them. The thing with flavors too, don't go by reviews and descriptions alone. Always order sample sizes first. It will cost more per ml, but you wouldn't wanna blow your budget on bulk flavoring that you can't stand. Also, don't stock up with somebody else's "essential must have flavors" list - if you do, you'll end up with bottles that never get opened. Find some recipes you wanna try and order stuff for those - eventually, you'll have your own list of must haves. Keep an eye out for sales and coupon codes - I get mine by getting on mailing lists.