Is there a way with just wifi to hook wireless (landline) phone into laptop and use googlevoice to make calls?

It is technically possible? Actually, yes. http://www.magicjack.com/plus-v05/ You will not be using Google Voice, but the concept is the same.

You need some sort of VOIP terminal adapter. One of the better known ones is MagicJack, which is a USB adapter with a standard analog phone jack - connect this to your wireless phone, and make calls via VOIP through your computer.

yes      using a VOIP adapter  for any analog telephone to plug into....usually cost under $26  and will work on nany PC usb port which in turn will allow a cordless telephone handset to work

There are many cheap ATA's that you can use for this, starting with an old expired magicjack device for about $10-15. The original version plus into an empty usb let and had a regular telephone connector on it. Then you can use and wired or wireless telephone to make or receive calls through googlevoice. Many people throw them out and either upgrade to a newer magicjack version, or move to another type of similar device, like that from nettalk. eBay is full of these types of adapters.