Are you using a Quick Change Tool Post (QCTP)? If you don't have one already, that's the first item you should have. A very few diehards use the old lantern toolholder, but it is a royal PITA that you'll quickly grow tired of.
Your QCTP will accept toolholders up to a certain size, like 1/2 x 1/2. You can often find larger toolholders on eBay & mill them down, but it's easier to start with shanks that fit the QCTP.
ENCO, MSC, J&L, Victor Machinery, etc. often have these on sale for not much money.