You must list anything you send in a package for dustoms forms. That being said, when i was in England my mom sent me a box with non-perrishable food items about every two months. she spent about 50-60 dollars in postage for a good sized box with lots of food items - instant thai noodle dishes, dried cherries, instant rice mixes, etc. The cost is high as the weight adds up quickly, but as long as you fill out the customs forms properly and there arn't any perishable items, they should get there fine. I found big boxes such as these could take up to two weeks by air mail, but usually closer to a week and a half. i got every box that was sent to me and it was always a nice reminder of home.
My mom even had a box of florida oranges and grapefruits shipped to me in Essex and though it cost her a small fortune, it got to me just fine. My British friends thought my mother was insane, but I love it! I wanted to ship a box to my fiance's family for christmas, but unfortunatly they arn't allowed due to the potential to spread some new kind of citrus tree viris or something. bummer. :-/