I have a 32gb ipad and from what I've heard, read, figured, etc it can accomodate an internal gps antennae from a 3g+wifi model. Any idea where to source something like this from (diy repair site or something) or am I better off looking for a broken 3g+wifi model to steal it from?

Rokr

A WiFi iPad cannot receive GPS. The RF (radio frequency) circuitry required to receive GPS is at a similar frequency to that used by 3G. As a result, the chip (semiconductor) manufacturers incorporated this RF circuitry into the 3G chip set and associated electronics. Therefore it is not possible for a WiFi iPad to receive GPS - but you can get external units that connect to the iPad.

Tim

You'd need to do more than add an anttena. Though you might be able to rig the extra circuit boards, you would still be left with the need to cut the case to add the plastic window for the radio.

There are teardowns on ifixit.com that will show you the differences:
iPad 2 Wi-Fi Teardown - iFixit
iPad 2 3G GSM & CDMA Teardown - iFixit