The meals, Squid bit - Cooking 65- Heals 17 exp 121. Nice caviar- Cooking 65- heals 16- Magic is boosted by 10%. The head cannot be traded but can be assisted. It can be RS gold traded once cooked. Squid piece and caviar could be traded cooked or raw.
To collect sparagar simply search runescape, it grows at random points in arbitrary farming patchs. This will not replace your crops simply add something extra. To discover if sparagar is growing in your crops talk with one of your scarcrows and they'll tell you where one buy RuneScape gold is growing, which you'll be able to harvest as though it were another herb.