The reason you aren't finding easy examples for how to do this in T-SQL is that it is generally considered bad practice to implement formatting logic in SQL code. RDBMS's simply are not designed for presentation. While it is possible to do some limited formatting, it is almost always better to let the application or user interface handle formatting of this type.
But if you must (and sometimes we must!) use T-SQL, cast your int to money and convert it to varchar, like this:
select convert(varchar,cast(1234567 as money),1)
If you don't want the trailing decimals, do this:
select replace(convert(varchar,cast(1234567 as money),1), '.00','')
Good luck!