there may be vga to hdmi adapters but quite frankly i'm not sure if sound can be carried via vga. i suppose you could output sound via a 3.5mm cord to a 3.5mm auxilliary audio input port on your tv if it has one.
but..
the simplest option would be to get a cheap card with either:
dvi output which supports sound out via dvi. you would need the propper dvi to hdmi cable then. this is how i personally connect up to my receiver.
hdmi output and a hdmi cable. i believe the cards with hdmi automatically support sound out but you might want to check on this.
most likely even low end video cards in this day and age support these features since htpc's and hdtvs as monitors are getting more popular all the time. for non-gaming use products...