www.SGAmmo.com is a great place to buy from. I just got almost 500lbs. of ammo from Sam last week and have order hundreds of pounds in previous orders. One was almost 700lbs. Always fast, ships out the same day most times and always exactly what I ordered. He's usually cheaper than other places once you figure in shipping. He has cheap flatrate shipping. Those places that claim to have free shpping like for instance Target Sports or ammo man have "included" shipping. Big difference. All they've done is tack on shipping charges and call it free and most times when you compare their prices you'll see that's what they've done. It's a marketing ploy for people who don't know better. That's where www.gun-deals.com comes in. It's a great place to make comparisions for just this reason. Keep in mind that the shipping quotes are just estimates on gun-deals unless it states it's flatrate or free. You always need to double check the vendors price for shipping.
One other place that's good too is www.aimsurplus.com They have some real good prices and shipping is fast also. They're in Ohio. Lots of neat stuff for sale including some neat mil-surp firearms from time to time. Oh and if you use reloaded ammo www.freedommunitions.com has some really good prices. They just ran a special on for 10% off of everything on the site on your first order and will most likely be running it again this month some time. They have 9mm 115gr FMJ reman. for $155/1000rds. With the sale they were $138.50/1000rds + shipping. One thing to note is they ship out of Idaho but some of the stuff they sell is so cheap it more than makes up for the extra shipping.