I had my MDF delivered yesterday. I ordered 6 sheets of 4'x8' in anticipation of also building subs and surrounds for my next projects.
For anyone that might be in North Carolina, South Carolina, Virginia, Georgia, or Florida, you might want to check out OrderOnsite.com to see if they service your area. They are a building supply company that offers free delivery in select areas. I had seen them mentioned elsewhere on the forums, but I was skeptical about using them. I figured a 6 sheet order of MDF would make for a good trial run. Well, they delivered the sheets the next day. What's more, the cost per sheet was actually ~$5 less than the big box stores. If you factor in the $60 truck delivery fee from the big box stores I saved $90... and yes this was a residential delivery. I do not have a truck, but even if I did I think I would still use them just for the convenience. The only problem with the service is that they do not give you a delivery window. I think the website says that they try to make it by 2pm, but my order arrived around 5:30pm. I work from home so that was not an issue, but it is something to be aware of.
(dts, I accidentally posted this in your thread also thinking that I was in my own. Hopefully more people will benefit)