I haven't actually made meatballs with grape jelly, but I've certainly heard of them, and that they are very good. Congratulations on your new toy!
Here are a few of my favourites...
Bargain Beef Stroganoff
1/4 cup \tall purpose flour
1/2 tsp\tblack pepper
2 lbs\t\tstewing beef, cut into 1-inch cubes
1 tbsp\t\tvegetable oil
8 oz\t\tsmall white button mushrooms, cleaned*
2 \t\tonions, thinly sliced
1-1/2 cups\tbeef stock
3 tbsp\t\tWorcestershire sauce
3 tbsp\t\ttomato paste
1 1/2 tbsp\tDijon mustard
1 cup\t\tsour cream
\t\tHot cooked egg noodles
In a bowl or plastic bag, combine flour, salt and pepper. In batches, add beef to seasoned flour and toss to coat. In a large non-stick skillet, heat oil over medium-high heat. Add beef in batches and cook for 5-7 minutes or until browned on all sides. With a slotted spoon, transfer beef to slow cooker; add mushrooms and onions.
In a 2-cup measure, combine beef stock, Worcestershire sauce, tomato paste, paprika and mustard, mixing well. Pour into slow cooker.
Cover and cook on LOW for 8-10 hours or on HIGH for 4-6 hours, until bubbling. Stir in sour cream and serve over hot noodles.
*can substitute large mushrooms, quartered.
Cheeseburger Sloppy Joes
2 lbs\t\tlean ground beef
1 medium \tonion, finely chopped
1 stalks \tcelery, finely chopped
1 can (10 oz)\tcondensed tomato soup
2 tbsp\t\ttomato paste
1 tbsp\t\tWorcestershire sauce
2 tsp\t\tdried Italian seasoning
1 cup\t\t1/2-inch cubes cheddar cheese
\t\tSalt and black pepper
4-6 \t\tkaiser buns, split and toasted
In a large non-stick skillet over medium-high heat, cook ground beef, breaking up with a spoon, until browned. With a slotted spoon, transfer meat to slow cooker.
Add onion to slow cooker, along with celery, tomato soup (undiluted), water, tomato paste, Worcestershire sauce and Italian seasoning, stirring to combine. Cover and cook on LOW for 6-10 hours or on HIGH for 3-4 hours.
Reduce heat to LOW. Add cheese cubes. Cover and cook for another 10-15 minutes or until cheese melts. Season to taste with salt and pepper. Spoon mixture over half a kaiser bun and top with the other half.
Homestyle Pot Roast
1/4 cup \tall purpose flour
\t\t**salt and black pepper
1\t\t3-4 lb beef cross rib or rump roast
1 tbsp \tvegetable oil
4\t\tcarrots, peeled and sliced
4-6\t\tpotatoes, peeled and quartered
1 cup \t\tbeef stock**
1 small can (7.5 oz)\ttomato sauce
1 clove \tgarlic, minced
1/2 tsp \tdried thyme
1 \t\tbay leaf
\t\tSalt and pepper
In a bowl, season flour to taste with salt and pepper. Pat meat dry and coat on all sides with seasoned flour.
In a large skillet, heat oil over medium-high heat. Add meat and cook, turning with a wooden spoon, for 7-10 minutes or until brown on all sides. Transfer meat to slow cooker.
Add onions to slow cooker, along with carrots, potatoes, stock, tomato paste, garlic thyme and bay leaf. Cover and cook on LOW for 10-12 hours or on HIGH for 6-8 hours, until vegetables are tender.
Remove pot roast, onions, carrots and potatoes, cover and set aside. Discard
bay leaf. Tip slow cooker and skim off any excess fat from surface of gravy; season to taste with salt and pepper. Pour gravy into sauce boat. Slice roast, arrange on a serving platter and surround with vegetables. Serve with gravy.
**It works wonderfully well just as is, but on my second go, I made a couple of changes which I liked a lot.  I used meat tenderiser on the meat and omitted the salt from the seasoned flour;  I substituted red wine for half the beef stock. These were beneficial, in terms of both flavour and tenderness.
In all cases, it has been my experience that the longer cooking time on LOW is definitely preferable to the shorter one on HIGH.
These come from a really fine Crock Pot cookbook, which I have learned to trust implicitly on the subject!
...here are the particulars, in case you are interested...
"Canada's Best Slow Cooker Recipes"
The publisher is Robert Rose, Inc., Toronto
$18.95 US $19.95 Can.
In addition to lots of interesting recipes, which so far have not revealed a dud, there's a good introduction and general information about slow cookers, and the principles that apply to slow cooking. As a starting place, it's excellent.
As a matter of curiosity, I checked Amazon.com for this title. There is one, "America's Best Slow Cooker Recipes", by the same author, with a similar ISBN, and the cover is identical. Guess there's an American edition! Here's the URL...http://www.amazon.com/exec/obidos/AS...591105-7776068
Anyway, there you are. Happy crockpotting!