You should get a reloading manual and study it. There is always a great deal of info besides just reloading recipes and you'll learn a lot about the craft. That said, Hodgdon does have all their info online and they make great powders.

Bullets: Summers Enterprises has great prices.

Shells: I like Reloading Valley, who pull apart amo and sell the components for pretty cheap. That said, Starline brass is the industry standard and by all accounts makes top quality brass.

Powder: I highly recommend you use a bulky powder when you start, because the most dangerous mistake a new reloader can make is double charging a bullet. If you use bulky powder, a double charge is difficult r even impossible depending on the powder. Trail Boss is perfect for new reloaders, because you basically fill the cartridge up with powder and that's your recipe (sorta - Hodgdon has recommended charges, but they basically fill the cartridge with powder).

Primers: I use what ever I can get locally, which is CCI. They have worked fine for me.

Key is to pay close attention to what you are doing and don't cut corners. Reloading is pretty fun but can be very dangerous if you aren't careful.