Well there's two ways to do it: new or vintage, and I'd generally recommend the latter.
In the case of the former, there are three big names, Dovo, Thiers Issard and Revisor (not quite sure what the deal is with Revisor - they may be new as in new / old stock - Mikael will know). I've nothing against Dovo inasmuch as I shave with one quite often and like it, but it's probably fair to say that their quality control has left a bit to be desired over the last few years, and the blades can be, ahem, problematic to hone. TI have plenty of fans, but so do Revisor ... in any of these cases expect to pay upwards of £70 for a basic razor, and the chances of it being in a fit state to shave with are remote unless the vendor specifically states that the razor will be supplied shave ready.
For vintage, that's pretty easy. Have a look at
Neil Miller's site. He doesn't have any cheapies up at the moment, but if you PM him here he'll be able to advise. A basic razor from the last century will be cheaper than any usable new one, and it will most definitely be shave ready. I'd suggest something like a Kropp or a C F Ern of some sort, or any of a few dozen other names - good reliable blades which will generally outperform most modern ones. You will have to budget for a strop as well, but don't be spending too much on that to start with.
For advice on sizes, type of grind and so forth there's lots of good information in the Straights area of the forum - don't be afraid to start a thread there if you want to clarify something.