said by dandelion:Am a little confused what you mean by insert.. i.e. some tables have an indentation that you lay the glass in, I haven't had many of those but have had quite a few tables with glass added to them. Simply make an exact copy using cardboard of the table top, go to any glass place and pick what kind of glass you wish to cover the table top with. Any local glass company can help.
If you are talking of a simply glass coffee table.. not glass covering it would be best to order one online if the store doesn't have it.
Talking about the table where the glass lays flush with the table, i'm sure you have seen those type, and not the type with a beveled glass.