I need guidelines for making beef stock with bones

I am pretty lazy and I make a lot of stock. I just take the bones and cover them with water in my crock pot and cook on low for 18-20 hours. I add about a tablespoon of apple cider vinegar, some salt, some garlic and some fish sauce. At the end, the broth is a rich, golden amber color and all the healthful gelatinous stuff from the marrow is dissolved into the broth. Then I store it all frozen in 1 or 1/2 cup servings in the freezer to thaw as needed. I use it for everything that requires water - rice, lentils, quinoa, etc.

Thank you all very much for your help !

Forgot to add the link: http://culinaryarts.about.com/od/stocks/ss/brownstock_1.htm

This is a handy step-by-step that I think answers most of your questions. It includes adding a mirepoix (carrots, onions, celery) to the roasting process.

Yes, roasting the bones adds extra flavor to the finished stock and a richer color too. Don't forget to add a splash if vinegar to the water, which will help draw out the bones' nutrients.