Park Seeds has seed starter sets, that are essentually a float tray system. They come complete with bottom tray, cell blocks, growing sponges (soil), and top cover. Not exactly inexpensive, but reuseable, and the soil plugs can be bought for subsequent years.
as an example
http://parkseed.com/parks-double-bio-dome-with-80-jumbo-cells/p/96039/
I have used the 120-cell system for many years for annuals - works well. I tried it a couple years ago with tobacco, but I think the cells were too small and too close together, and the 80-cell system would work better. But it did work for me, and I may do it again. Check out their website - they have a wide range of systems available.
Several things I've learned using these:
The top cover is useless - don't need it, the soil plugs absorb/retain enough moisture for seed starting. Using the top cover creates too moist an environment and increases potential for damping-off or mold. But it may be needed in a really dry climate.
Just water in the bottom tray is sufficent to start seed. After the first true leaves appear and are dime-size, fertilizer at 1/8 to 1/4 strength can be added to the water. More than enough until they go in the ground.
The soil sponges are great - no need to create your own soil mix.
Since 100% germination cannot be expected with tobacco seed, I recommend 2 or 3 seeds per cell, then just pick out the extra for one plant per cell. Since the soil sponges are a homogenius block (not loose soil), and the root grows into the sponge, they can't be picked out to re-transplant.
Since the sponges are a solid block, they can be pushed out of the cell and re-located to another cell, if desired.
When the cells are planted in the ground, the top of the sponge needs to be covered with soil. They're just like those peat 'Jiffy-Pots' - will wick and evaporate too much moisture from the soil.
The only reason I don't use this for tobacco any more is that I want to be able to start multible seeds in a pot of loose soil, so I can transplant all viable sprouts. It is a very convienient and complete system, good for newbies, as you don't have to re-invent a seed starting system from scratch.