Do you want a dedicated port or dedicated bandwidth? The port should cost nothing, really, that's the provider's choice if they have respectable hardware and routing. If you want 100mbps of internet bandwidth, don't pay anything over $4,000/month, and definately don't pay anything under $900/month.
$40/mbit is respectable for premium bandwidth (ie. InterNAP, Peer1)
$9/mbit would only be single-homed Cogent, which would be a garbage network and not for anything mission-critical, but usable.
You will see a lot of companies that offer '100mbps unmetered' outside of what I just described to you - they're called oversellers. They may have 100mbps of bandwidth, but it probably won't be available to you - you're going to be fighting all of their other customers for the same usage (which typically ends in very bad packet loss). But probably, you'll never use enough bandwidth to notice (and that's what those people are counting on), 100mbps is a huuge amount of bandwidth, and definately unnecessary for web hosting.