Maybe you are fishing the wrong type of water if you can't get a good feel for the bottom. For example, at Blue Creek on the Cowlitz you are lobbing an ounce and a half just to get down to the bottom and halfway through your swing the current forces you gear to the surface. That is a difficult area to fish for a beginner.

Reading water is actually half the battle. In my experience, you aren't going to find fish holding at the head of a run where it is boiling anyways. Steelhead are sort of lazy. They will hold lower in a stretch or in a tailout where the water smooths out and slows down. In that type of water I would be surprised if you would have difficulty reading the bottom and differentiating that from a strike. Once you get a handle on the feel of a strike you can look for fish in more difficult water conditions.

Try adjusting your weight for the depth and speed of the water. I always try to start out with more lead than I need and trim lead length for each drift. Incedentally, I am a slider rig fan. I believe you will be able to feel the fish sooner without having to wait for the current or the fish to pull the slack out of your line and pickup the lead to transmit the resistance to your rod.

For a different approach try ignoring the tapping of the bottom altogether. Instead leave the line just barely slack. You will see (on a shorter cast) the belly of the line bouncing from the bottom contact. As you watch the belly of the line, lift your rod anytime the line stops drifting or comes tight. If it is the bottom, a flick of the wrist should get it drifting again, if it is a fish you will probably know. Don't be afraid to set the hook if you have any doubt. Better to strike on a snag than miss a fish.

There was an excellent thread about this called " I have lost all abitlity to feel the bite" from back on 9-22-03 that covered this better than I can explain. Do a search on the Forum and check it out.
Good luck