Did you also try to set up a wired network through VASM? Do the settings you're using match the settings on the host system (Windows? Another Linux?). Remember that you need to identify your network card as what the *virtual machine* emulates as a network card. In other words, not the actual network card you're using, but the emulated card. It's like that for most hardware in a virtual machine. Linux thinks the hardware is what the vm emulates, not what's actually on your computer. I'm not totally sure that the other settings (IP address, gateway, etc.) have to match the settings on your host system. You may find out in the documentation or a user forum for VirtualBox, if there is one. But I AM sure that you need to set up for the emulated network card in VBox, not your actual card.
I had a similar situation back in August to November, 2007 or so, when I got a new laptop and VL 5.8 would not work wirelessly with my new computer. In order to connect, I set up a VirtualBox vm under Vista. Vista was actually using my wireless connection, but in VectorLinux I set it up for the emulated wired network card. This worked very well.
I don't remember any more details. I just know that VL in VirtualBox allowed me to use VectorLinux for those sad months until I was able to get wireless working on my "real" VL partition at some stage in the development of VectorLinux 5.9 Standard. Once wireless was working in VL, I stopped using the VirtualBox vm in Vista.