Hi,
Unlike some areas, mine is not a haven for reloading supplies at the LGS. A few have a reasonable stock but at outrageous prices, while some have good prices on empty shelves or simply don't handle such products. So most of my supplies come from online sources. My favorites include Powder Valley for powder and primers, Graf's for bullets and rifle brass, and Starline direct for pistol brass. Most of my shotshell supplies come from Ballistic Products. MidwayUSA has also been on the favorites list for a long time for just about everything shooting related, both reloading and other.
One thing to remember if one's new to buying shooting/reloading supplies online is that if prices are a consideration for you, as they are to most of us, be sure to compare what it will cost to get the order to your doorstep when there's a choice of vendors with the same product. Some vendors have better catalog prices but higher shipping, while others with higher catalog prices make up the difference with lower shipping charges. And haz-mat fees must be considered for any powder or primer shipments, so it pays to build up a good sized order when a haz-mat fee will be required (BTW, while primers and/or powder by themselves incur a haz-mat charge, primed brass and loaded ammo don't.)
Also, a growing aggravation with online purchases is that, depending on the vendor, items being purchased, and buyer's place of residence, the vendor may require additional documentation to be on file prior to ordering ammo, powder and primers. Or they may simply refuse to ship to your area, too, depending on where you live. Sometimes that refusal is based on black letter law, other times on the fact local laws are just too much trouble for a vendor to try to keep up with. If that's a problem, please take it up with the people who made your laws, don't give the vendor grief!
Rick C