(Google Docs) Finding Data - writing & sum

Hi all,
First off, wow! You all have so much knowledge about database/spreadsheets. I've been reading lots, and found lots of great info. Awesome site!

ok here's my problem, which I hope is no problem for some of you smart cookies

https://docs.google.com/spreadsheet/...hl=en_US#gid=3
is my spreadsheet- which if doing everything right you should be able to see but not edit.

What I'd like to be able to do is collate how many 'beetroot'(food items) I have harvested (currently) down in the area at the bottom. I'd like the file to be able to search out all the entries of 'beetroot' and then add them all up for a total number - savings and weight of 'beetroot'.
Also if it is possible I would love it that if I add say 'carrots' at the top the file can register I don't have that listed in the 'collating' area and go ahead and write that for me. - Don't know if that isn't a complete stretch of imagination lol.. Do I need to put the 'collating' area on a different sheet? or perhaps up the top? This stuff hurts my head
Thank you for any help or advice you can give me.