CrossRoads:
Easy to bootload blank chips with westwf's optiload program tho. I stocked up some last time Newark had low prices.
Currently $3.42 for 10.
$3.31 for 10 at Mouser
http://www.mouser.com/ProductDetail/Atmel/ATMEGA328P-PU/?qs=sGAEpiMZZMtVoztFdqDXO6rEZqxeooRg
$5.50 for 1 seems high.
If you live in US-midwest and don't mind getting 25 of them:
$3.12 each for 25 pcs.
Even cheaper. The 25 that I bought, which seems to take forever to use up, did not last very long. They all got their phi-panel firmwares and were shipped out. Only 5 are left. Besides westfw's optiloader, I also recommend xloader to upload hex sketches. Way faster than arduino IDE and compact size. Perfect for in the field reloading sketches or firmeware updates, which is what I do with it.