First of all:
1. Geoff Tate (Queensryche)
2. Eddie Vedder (Pearl Jam)
4. Chris Cornell (Soundgarden)
High Baritones
3. James Hetfield (Metallica)
5. David Bowie
7. Robert Lunte
1. Nick Cave (& the Bad Seeds)
3. Ian Curtis (Joy Division)
Standard Baritones... but I'm not sure about Robert.
8. Axl Rose (Guns & Roses)
1. Ville Valo (HIM)
Low Baritones.
Rest of them, you can probably check on The Range Place.
Secondly,
There aren't many low voices in Rock music, but you can try:
1. Billy Gibbons (ZZ Top)
2. Peter Steele (Type O Negative)
3. Neil Fallon (The Clutch)
4. Alex Band (The Calling)
5. Warrel Dane (Nevermore)
Thirdly,
If you want a serious challenge, try to emulate good singers. I don't want to sound offensive, but low voices, generally don't sing very well. So... get some low tenor... Bon Jovi for example. Lower key of his song for about... you are bridging on d1, as I remeber? Bon Jovi is bridging on f#1. So, it will be 2 and half steps. After this just... start singing If you can emulate his setup, than you can claim victory. Of course, for Queensryche songs it will be one step, for Metallica half etc. Why do this? Passaggio for each voice is different, so it's better to sing at the same register, as vocalist that you are emulating. Good singers didn't sing above their limits, because it never sounds good (Except very good vocalists, who are singing maximum one step higher than theirs voices... two, if song is easy).