The cheaper the receiver, tend to be lesser in power and lesser in options. I usually avoid low end receiver under $200 unless it's an older model, refurbished, or on clearance. Usually, I stick to the middle of the road type of receiver, $400-$600 range.
Denon's and Yamaha's mid range receiver should be more than enough to power most speakers. Onkyo often offers great bang for the options money can buy but over the years, Onkyo's quality have diminished to the point, I have no faith in their quality. I've owned two Onkyo, one low end; one mid-range and both begin to failed less than a year into owning it. The more research I did, I found their quality lacking. I've owned a Harman Kardon receiver for quite some times now with no issues but I have read plenty of complaints from Harman Kardon owner's as well.
Pioneer Elite and Marantz are also options as well as far as receiver goes. Best bang for the buck are usually close out models from the previous years or refurbished receivers. My Harman Kardon and Marantz receiver were both refurbished and I have them for well over 5 yrs now. Where ever you buy your receiver from, especially if online website, make sure that seller is an
"Authorized Dealer" for which ever manufacturer you chose to buy. Or your warranties will not be valid.
Out of your $3K:
$400-receiver
$600 for 1 subwoofer
$2000 for 5 speakers.
You can purchased your wires, cables, connectors, HDMI, etc at
www.monoprice.com. I've used their stuff for my three home theater systems and have no issues in all the years I've own them.
Subwoofer: These two subwoofer brands are often associated with good bang for the money. Get at least a 12 inch subwoofer.
www.svsound.com
www.hsuresearch.com
As for speakers, the options are limitless. There are just so many brands you can look into. You'll just have to go and audition a few brands local to you and pick which one you prefer within your budget. If you know what brand to look for, the best deals are often found used in craigslist.org. I've found some amazing deals in there over the years. A few years old speakers that was once sold for thousands can be had for 50% or more off from the price when it was new. But you have to know what you are looking for and don't end up getting scam for one of those phony imitation/knock off brands; also known as "White Van Scam".
Go here to read up on home theater, speakers, receivers, subwoofers, etc:
www.avsforum.com