it makes little (no) difference what os you are using with regards to your hosting company... or the other way round...
just get a decent mac ftp program and you should be sorted. if you're getting a bit advanced you will need something like putty for shell access. but i think mac has something like that built in? (should do ... based on unix) and maybe some db interface - but phpmyadmin should work fine (and is browser based) if you use mysql......