Got all the parts in today, not bad considering they were not scheduled to be delivered until June 19th. Unfortunately I didn't read well enough and the 4 wire load cells I thought I was ordering were actually only 1 single 4 wire load cell. So, that isn't going to work at all.

Fortunately, what is going to work is the other 3 wire load cells I ordered. They came in a nice pack of 4 and I think I can make them do exactly what I want.

I also ran across some really great articles on using the HX711 directly with the Raspberry PI, so no more need for an Arduino in the mix (yea, less parts)!

Just in case its useful for others, here is what I have found so far:

http://hivetool.org/w/index.php?title=Interface_the_HX711_to_Pi (HX711 with the Pi)

https://github.com/ggurov/hx711 (HX711 library for the Pi)

Hopefully over the next couple days I can figure out how all this is going to go together and then I can get on to devising how exactly I plan on using it :)