While I respect the programs NullRiver puts out their tech support really bites! I purchased the killer app "Tuner" from them and loved the shear amount of stations they had, even police scanners. They released an update that made it sound as if they did a better job with the app and true, it was easier to navigate but most of the stations where gone! Where a search for scanners had over 100 hits before there are now zero. At least the one station I bookmarked still works.
Let me start by saying my biggest pet peeve is "updates" that make no mention of features that have been removed. I HATE THAT.
FWIW, iTunes currently doesn't do a great job of "cleaning up" after you download updates. There's a good chance that in your ~/Music/iTunes/Mobile Applications folder, there's a Tuner.ipa. Tuner 1.ipa, Tuner 2.ipa, etc.
What I'd do in your case, is try to install an older version. Drag it into iTunes and overwrite the newer one. Use it. Bookmark the scanner streams you like.
Then, update to the newer version as usual and see if your new bookmarks, too, still work.
No guarantees this will work for you, or how long it's even a valid loophole. It's possible iTunes 7.7.1 fixed some of the "update mechanism" bugs, like this one.
But I just figured it was worth mentioning, in case you hadn't thought of it. It just might work.
Shame on Nullriver for not getting back to you, and worse, for "updating" the app and quietly removing features you enjoyed.