This one: https://www.sparkfun.com/products/10245
Those are used in person weigthing scales.
A load cell is typically a aluminium beam with holes.http://www.ishida.com/technologies/loadcell/html.html
Load cell on Ebay: http://www.ebay.com/sch/i.html?LH_BIN=1&_sop=15&_osacat=0&_from=R40&LH_PrefLoc=2&_nkw=load+cell+aluminium&_sacat=0
Most have 4 wires, I think that is better against temperature influence and noise.
But since they are on Ebay, I don't know how accurate they are.
Perhaps in your country is a webshop for load cells.
You could also buy a digital persons scale at a garage sale. I think 80% chance it has a load cell.
Why is resetting to zero a problem ?
Do you want absolute weight measurements at any temperature without the need to reset it to zero ?