What RAZR do you have? Which service provider? Assuming you don't have one that cannot sync with Macs / is not enabled by the provider (e.g. Verizon / V3m, which I think can only do a couple of limited things), it's pretty straightforward. There are step-by-step directions:
Egh, yeah, it isn't great, but it's functional. The V3 also doesn't store very many numbers. I think those things are better in the later phones.
For what it's worth, in my V3, to make it discoverable, go to settings -> connection -> bluetooth link -> and you can do it there.
Oddly, I just looked at that place on my phone, and it said "Bluetooth module not connected!" And it would not connect to my iMac! However, turning it off and back on seems to have resolved this issue. Strange. Never had that happen before.
You should be able to click on the bluetooth icon and use either send file (and then send the file) or use browse device (and then just go the appropriate folder and put it there. I sent a number of MIDI files to my RAZR for ringtones, as well as a JPG that I used as wallpaper. If you do send file, you'll just accept them on the phone and then save them as sounds / images / whatever. I just sent an MP3 file, which also worked fine. After you accept the file for transfer, you'll get the option to store it and/or immediately apply it as a ringtone / wallpaper (depending on whether it's a song or a pic).