I have been using Meguiar's Natural Shine (?) and it is good if you don't want your tires to look like polished paint. It has a higher viscosity than most (but not all) other 'rubber dressing' products, but it isn't nearly as viscous as Endurance. There is no sling if you let it sit for about an hour after applying it before you hit the streets. Otherwise your best bet would probably be Endurance. You can get either product just about anywhere... I've even seen them at Wal-Mart and Target.
Griots rubber cleaner is also good to use before putting dressing on. Lots of people put dressing on dirty or untreated tires and it just doesn't look the same.
I used STP's 'Son of a Gun' rubber treatment for a long time and I really liked the way tires looked after using it, but I don't think it's available anymore. I've been looking for 303 but I don't think there are any retailers that carry it around here (?), so I guess I'll have to buy it online. It has had many good reviews as well...
Good luck,
--SONET