I'm assuming I couldn't use it on myself, so I'm wondering if my dh could learn to use it. Also, there are ones for $15, and ones for $100+, anybody know if there's a huge difference in quality/ease of use?
It's not hard at all! The hardest part is waiting til your baby is big enough to hear faintly, which IME, using one through 3 pregnancies, has been 18-20 weeks. At 26 weeks it's now much louder, though how loud depends on the baby's position. DH always finds it, counts the beats with his watch, and then I listen. So sure, you can use it on yourself.
Ours was about $20 through Amazon.com. It works great. I have to say, it is always a very bonding experience for my DH before the baby is born. The baby will kick at the fetoscope, it's a fun game!
We got that under $20 one on Amazon too, and figured it out the first night. I think it worked around week 18 or something, but it's hard to remember. If DH does the forehead thing, I can listen through the earphones and hear the babe. These days I can hear the babe on my own, just by pressing the end in with my hand.
Our baby kicked the fetoscope too.