This is a tough request and is an issue that I myself have been frustrated trying to figure out. Part of the issue is that there are multiple algorithms for estimating IBUs (e.g. Rager, Tinseth, Garetz) - each will give you a different estimate depending on when the hops are added. So the EXACT SAME hop schedule can give you 50 IBUs on one, but only 35 on another.
Another issue is that the same hop schedule brewed on your system will end up with a different bitterness on my system (not to mention a commercial system) due to water chemistry, kettle size/geometry, yeast, etc.
I guess what I am trying to say is that the only way to really get a handle in this is to brew some beers using a consistent IBU estimation algorithm (I use Rager) and figure it all out relative to to your system. For example, after brewing a bunch of beers, I now know what 25, 35, and 45 IBUs tastes like coming out of my system. I could tell you that Bass Ale is 20 IBUs, but someone else will tell you its more like 30. And we'd both be right because we're comparing it to our own system.
