Craig North Carolina
Look at the Grade Crossing Pro from Logic Rail Technologies. For two tracks you would need two separate GCP boards, but they come complete with sensors for one track. You also have the option of using infrared detection or photo resistors. Choose infrared if you have a dark layout room.
http://www.logicrailtech.com
Check out Berkshire Junction. They have a wide selection of crossing signals and control systems. I bought their signals and Infrared control system as a package deal for about $50.
There is a short 'How To' on the installation of my crossing signals and control system on my website. Just push the 'How'd You Do That' button and scroll down to the thumbnail of the RR Crossing.
Or you can try this link: [url=http://www.intergate.com/~acoates149/CR.html]
My Berkshire Junction signals have been in place for 3-4 years now and have operated flawlessly.
Good luck whatever you decide.
Remember its your railroad
Allan
Track to the BRVRR Website: http://www.brvrr.com/