Fair enough. I can only imagine how de-tuning a non-baritone guitar by 3 full tones would sound as I have never felt the need to do it. I have a bass. Although from your MySpace samples, you should have no worries mixing a kick to stand out amongst those guitar tones, a bit of EQ to bring out the attack and you'll be fine.
Your standard western kit isn't tuned to a pitch. Never. Never ever. Pitched percussion does exist, as orchestral timpani for instance, but I can guarantee you it's not something that Chimaira do. No drummer, engineer or producer will tune a kick drum so that it's fundamental frequency matches that of a guitar, whether it's tuned to concert pitch or a dropped tuning. What you are most-likely identifying with is the particular degree of tensioning employed when fitting the skin to the tensioning rods of the kick drum. This shouldn't be thought of as tuning, though invariably an increase in tension will produce a higher pitch and vice-versa. The sound of a kick drum may be seen to compliment that of a guitar, though this is invariably the product of a well-conceived mix, not the matching of frequencies.
In answer to your sampling question, as a western kit is not a pitched instrument, it is highly unlikely that you will be able to specify a particular pitch when triggering a sample. You may - depending on the software and VSTi in question - be able to alter the tone of a sample, though as before, this is akin to simply increasing or decreasing the tension of a drum skin.
