Netbooks equipped with 3G wireless broadband are about to hit en masse given that Costco will carry a 10.1 inch Acer Aspire One  that comes with with AT&T mobile broadband, according to Costco training materials circulating across gadget sites. What’s more, Acer’s similarly-equipped Aspire One with an 8.9 inch screen has finally hit the $50 price point, TDR has learned.

The Costco kiosk will probably resemble a Verizon cell phone kiosk where a staffer (not sure if the person is from Costco or Verizon) sells phones and writes up service agreements. Presently, Costco sells a variety of netbooks online from$350 to $680 and without wireless mobile broadband. At my Costco in Danvers, Mass., the first thing customers walking through the door see are electronics and it’s likely the new Acer netbook will take their place next to the iPods and digital cameras.

For Acer’s part, it already sells an Aspire One with an 8.9-inch display through Radio Shack stores that is equipped with AT&T mobile broadband.  Radio Shack just dropped the price for the unit to $49.99 after starting it at $99.99 in early December.

The Costco training materials says personnel must take two courses (one is 15-20 minutes in length) and complete them by May 8 for the May 11 launch. Pricing for the Costco’s first 3G netbook could slide ride into the $80-$100 price range vacated by Radio Shack. I have calls into Acer and Costco and awaiting word when the West Coast go to work this morning.

Rock bottom netbook prices are subsidized by two-year service agreements that typically cost the customer $60 a month.