Windows Mapping software with GPS connectivity & text to speech

I'm after some autoroutesque software (that is, software a bit like ms autoroute) but one that reads out directions as you approach that point. do you know what i mean? in autoroute, if you ask it to generate directions it lists them, and with the gps connected and interfacing with autoroute i assumed you could get it to at least highlight the point at which you were at, but you just can't. is there any software that i can use alongside autoroute? i don't really fancy spending that much money...