I dont think netbios traffic is usually sent over a vpn. You should be able to access machines by IP though. I've never tried routing netbios traffic over a vpn but I'm sure it is possible. Just do (backslash)(backslash)ipaddress(backslash)sharename and it should go fine. As long as you have rights to the share of course
If you had an active directory domain setup at work you might be able to access machines via their full dns name. That is if the vpn server handed out the windows domain controller's ip for dns resolution.