A friend tells me that performance enhancing drug use is pretty common on the high amateur, almost pro level of bicycling. These are folks who are very good and obsessed with the sport, but not at the pro level. But there's also no testing at many of their races so they can get away with the PED use.
No one is really sure what to do because these dedicated semi-pros pay lots of fees to support the races. If they're a bit strict on PED use, the registrations could really drop off. But on the flip side, the PED use drives away others who are competing fairly but just not ready to submit their body to all of those extra chemicals.