I personally prefer the solely online sellers like Amazon and Newegg. If you buy from a store, sure there's no shipping cost or waiting, but in my experience the price in store makes up for the lack of shipping cost and kinda makes it worth waiting a few days to a week anyhow.
Halfway reasonably priced to me for CPU board and RAM would be around $550 or less. $200-$300 for a good cpu, and another $200 split between the board and RAM. You have to have a Z series chipset for overclocking if you go Intel though, so the only real way to save money there is to get Z87 instead of Z97 (for Haswell CPUs like the i5-4690k and i7-4790k) and I don't think there's a lesser Z chipset for Skylake (i5-6600k and i7-6700k).
Not sure of your budget, but in my opinion if all you need is cpu board and ram something like this seems good:
http://pcpartpicker.com/list/VVwxYr
With that you spent $430 on the parts you asked about, and for another $250-$300 you can get a GTX 970 to go with it. Some parts can be salvaged from an older rig like an HDD or sometimes you can re-use a case, assuming it's not a pre-built PC like an HP, etc.