I am looking into getting a dsiplay port adapter for my macbookpro and I am wondering if i get an hdmi one, will that force my audio through it? or can I just send video through it and still have audio through my speakers?
I'm running a MacBook Air, and I use a mini-displayport to HDMI cable to connect to a monitor. Audio still comes out through either the 3.5 mm jack or the speakers for me. That being said, since you need a chip to convert between displayport and HDMI, you may end up transmitting audio depending on what chip the cable/adapter uses. In other words, YMMV.
Also, as far as I can tell, a lot of MacBooks don't support audio over displayport. So you may be ok. :-)
If your monitor doesn't have an audio output, you simply won't be sending audio--there's nothing connected to the audio part of the HDMI cable. My HDMI cable plugs into a HDMI-to-DVI converter, which plugs into my (ancient) monitor.
Of course, you should be able to go into the OS X System Preferences and choose your speakers as the audio output device. For example, in OS X Lion: .
I'd buy a displayport to HDMI cable instead of a DVI cable--you can use the HDMI cable more places, and you can get the HDMI-to-DVI converter for really, really cheap (~$2-3 USD).