I can tel you if you want to buy a juicer that wil last you forever this is a good one. I am not sure if it has a wheatgrass attachment, but asa general juicer they are very hard to break. ours is 8 years old and still going good.
They are really good quality
http://www.championjuicer.com/
http://cgi.ebay.com.au/NEW-CHAMPION-... tem4aaa87371b
I dont have one of these atatchments but am considering it. with the champion juicer you just buy the attachments you need for the job.