On Saturday we did two things to help the tomato plants, which seem to have been stuck at the seed leave stage for the past month. First of all, we replaced the florescent lamps in the seed starting set up. We bought one plant/aquarium bulb which is at the red end of the spectrum and one natural daylight bulb in the blue end of the spectrum. I also transplanted the seedlings into larger cups. I split up the pairs of seedlings of each variety. One will remain inside under the lights, and the other will go out into cold frame. I'll know the lights helped if the ones inside do at least as well as the ones outside.
I may have to resort to planting seedlings from a friend and give up on mine if they don't take off soon.