Take the advice above to learn to grind (and hone) your own HSS tool bits. There's plenty of advice and instruction out there. You can easily experiment with shapes, angles and tip radii. You'll learn how surface finish, stock removal rates, chatter, etc., etc. alter with tool configuration and you'll understand why things are happening. You're then only a few steps away from being able to make tools from gauge plate or silver steel, for odd and special jobs. However, if you start equipping yourself with tipped tooling, it'll cost a lot, you'll need to navigate the arcane coding system for tips (most are unsuitable for lightweight, low-powered machines), and you'll need to understand what tip parameters are required for each application. Also, you'll cry when you find out how fragile they can be, especially in the hands of the inexperienced lathe operator. I'd also suggest that a tipped-tool-only user won't understand anything like as much about cutting as one who has gone through the HSS-grinding apprenticeship.
If you're determined to go the tipped-tooling way, I'd suggest going to someone like Greenwood Tools (no connection) who supply amateurs with a pre-filtered, small selection of holders and tips, which are suitable for 'our' machines and materials.
Another important consideration is the cost of a handful of toolholders and a selection of tips, compared to a bundle of HSS blanks. The considerable difference can be put to good use – on beer.