Pick a sample with a pitch not too far away from the key of your song (or it will only end up sounding hollow, at least if you need to pitch it up), if you have trouble finding one, see if you can find any sample with no pronounced pitch in the lowend.
Easiest way imo to tune the kick is to grab a synth and set it to a default sinewave, pitch it down a few octaves and play a bass note on the key that you want, and reference it while you pitch the kickdrum.
Then when you hear it's in key, grab an EQ and tame it so it sounds natural in its new key. I find that in 90 % of the cases where I tune a kick, I grab a sheet of the frequencies of the different notes, and do a narrow boost on the key that I have in my track, alongside cutting with a narrow bandwidth any harmonic close to the boost that may be in the way.
Again, if you pick a sample with no pronounced key, just tune it until it feels right (usually not much at all), and shape the tone yourself with boosting/cutting on the EQ.
Lastly, highpassing any rumble can clear out the kick and boost the key signature in it (but don't go too far or it will sound hollow and unstable).