Spinningbabies.com is a great resource. Any experienced midwife or doula will be able to help you identify baby parts as your pregnancy continues--they are often more skilled at this than other practitioners because they do not rely on ultrasound technology as much and have very experienced hands.
At 22 weeks, your baby is still doing some backflips and such, but pretty soon things will get crowded and the big movements will slow (although kicking, etc., will feel more intense as you run out of room).
My midwife taught me this when I was about 30 weeks: lay on your back and squish your bump. Find a big, hard lump and feel around it on either side. If it seems to go in and then back out, you've probably found the baby's head and neck. If it seems like it it is never-ending hard mass, you've probably found his bottom and back. You'll often feel the little tickly (or punching) movements on the opposite side of your belly from the bum-lump.
BTW, as you end your pregnancy, the ideal position is head down and facing your back. Since the heaviest part of the baby is the back of his head, you can encourage this position by doing pelvic rocks on your hands and knees and generally spending lots of time on your hands and knees. I made a point of playing with my son and cleaning the floors on my hands and knees during my second pregnancy, and that was by far my best and easiest birth.
Best wishes!