My hobby is the evolution of the English language since it got its start in the 5th century. Little linguistic variations are fascinating.
DON'T PUT A COOKED MEATBALL IN A STEW - IT WILL FALL APART. Meatballs should be eaten without further cooking apart from a little light heating by simmering in the (whatever) sauce you're using. Why would you put meatballs in a stew made from ground beef?? Stews need not be 'watery' unless you add too much water.
I'm not familiar with US meat prices so it's hard to comment. Basically cheap beef cuts need to be cooked longer to break down the tougher connective tissue. Slow cookers are good. I have a small slow cooker since I'm normally cooking for one. I bought it from the supermarket- it was cheap. There are two issues here:
Tenderness: slow cooking helps to break down cheap (tougher) cuts of meat.
Taste: depending on what I'm cooking I could add onions, garlic, bacon (salt alert) , red wine, curry, chili, various veg, canned tomatoes, mushrooms, beef stock (salt alert), herbs etc. - just like the ground beef stew.
Start with a simple recipe from the net. I'm not a fan of Irish stew but it may be where you could start. Beef Bourguignon is also good but a little more complicated (you'll need the wine).
After doing this two or three times you'll begin to see the possibilities of adding this or that and get a little confidence. Don't worry if you muck things up - I mess up regularly.
OB