I don't have a crockpot, but often slow-cook stuff in the oven or on the stovetop.  Slow cooking is so easy, and you almost can't ruin whatever you put in the pot – unless you cook it too high for too long.

What do you like?  Fancy some sausages and sauerkraut and carrots?  Just dump a jar of kraut (liquid and all) in the pot.  Add your favorite sausage (links, the bigger the better).  Add carrots and onions and garlic (fresh, whole, but cleaned and peeled).  Toss in a bit of salt and pepper to taste.  The big secret:  8-12 ounces of beer.  Cheap is fine because the alcohol evaporates anyway, but a good beer is better.  Turn the thing on.  Go play games for several hours.  Voila!  Dinner.  Add a good bread, and you've got a very hearty meal that can last several days (in the fridge) if your pot is big enough.

Like corned beef and kraut or cabbage?  Follow my instructions above, but use a corned beef brisket that you cut into 4-6 large hunks.  Use fresh cabbage (clean the outside of any dirt then cut into halves or quarters) instead of kraut (you can use kraut if you like it).  As above, carrots, onions, garlic, salt and pepper and beer.

Pot roast?  3 lb. beef chuck roast cut into 4-6 large pieces.  Carrots, onions, potatos, garlic, salt and pepper.  No beer, although I guess you could.  Over this pour 1 or 2 cans of beef broth or stock.  About an hour before you think the meat is cooked to your liking, mix a few tablespoons of flour in 1/2 cup of water and mix until most of the lumps are gone.  Then add that to the pot, stir, and wait until it has thickened into a gravy (45 min. maybe).

Use chicken (pieces or a whole chicken cut in half) instead of beef for the pot roast, and use chicken broth or stock.  All else remains the same, except that the cooking time will be a bit shorter.

xtal, those of us who have been cooking for a long time know that it's really hard to make mistakes with basic foods.  Overcooking in terms of time or temperature will ruin a recipe more than anything else.  With a crockpot you've got an almost mistake-proof appliance.  Throw in stuff you like and see what happens.  Sloppy Joes.  Pulled-pork BBQ.  The list of simple crockpot recipes is as long as your imagination.

Bon appetit!

By the way:  dont' get too good at this cooking thing, because if you do, those of us who may be sick of cooking might just appoint you Chief Cook in the silo.