The omni Wkhanna recommends is an excellent one, however, if you are really trying to get stations 100-150 miles away you will need a directional antenna. A BIG directional antenna. FM signals travel line of sight so the curvature of the earth will limit or prevent them from travelling that far. The height of the antenna certainly makes a difference, and there are atmospheric conditions that can help intermittently (when signals can travel hundreds of miles) but you can't rely on that. There are some very nice directional antennas available, try searching the archives for recommendations.
Excellent Outdoor FM Antennas
I'm interested in purchasing a highly sensitive outdoor FM antenna that's omni directional to pick up stations from 100 to 150 miles away. What, if any experience does anyone have on this list. Additionally, I own 2 very good tuners. The Magnum Dynalabs 108 and an older McIntosh Mr78. Both are exceptionally good in terms of sensitivity. Concerning the Mr78, I need to have it recalibrated and cleaned up. Who is recommended for such service?