Set your camera to DV mode. I am very frustrated with the users. They do not seem to be using the camera as they should for the money paid for them.
Check the menu settings in the camera - try adjusting them and see if that makes a difference. I used that camera to capture some HDV footage couple weeks back (pretty sure it was that model - it was a small HDV Canon with 30 in the model #) and it worked fine.
I know some cameras and decks need to be set up right before they will work with Premiere Pro, or any NLE for that matter.
If you are able to capture in iMovie, then make sure iMovie is closed down before trying to capture in PPro - that could be what's causing the problem.
HV30's (and XLH1's for that matter) can be finicky on the firewire capture side of things. I've had similar dramas in the past, I share your pain.
As Harm suggests, dig through the camera menu and set firewire output to DV (and not HDV/DV). That almost always sorts it out.
I also used to have a bit of luck by actually resetting the camera itself. from memory, the tiny reset switch (use a ballpoint or paperclip) is under the battery.