The most ecconomical thing to do these days, is to get the best deal you can on like an Onkyo 770 system, which includes a real nice robust AVR at it's heart. Then after you get it, start deciding what you want to change about it, sell off what you don't like, replacing it with something better that will make you happy.
There just isn't much that can touch the price -vs- performance of the Onkyo 770 system.
But for $1500, you have great flexability on hand picking components.
Start with the best Subwoofer you can buy and go from there.
I still like the Velodyne CHT-15 for $500 deals. I have yet to find a sub I think beats it for $500.00 or less.
Great higher end Mid-Fi 7.1 AVR's can be found inexpensive at places like etronics / 6Ave / ecost / ect..ect...
Pioneer, Yamaha, Sony, Denon, Onkyo, all make resonably decent gear. I tend to favor Onkyo, Yamaha, and Denon, but that is really just preference sorts of things, really I am a Denon head as some like to say.
After you decide on those two, then see what you have left over to devote to speakers.