IMO, I am sure those mini-greenhouses will work... if you want to pay that much. If they are the same ones I have seen around- they are pretty pricey. I use this kind of setup (Not this exact product, and I have never ordered from this company):
http://parkseed.com/72-cell-insert-for-parks-seed-starting-tray/p/96379/
The clear humidity dome and bottom trays I buy once and use over and over. I get the bottom trays from the local garden store for about $2.00 a piece, maybe a little less. The clear humidity domes I get for like $2.00. Sometimes I get this style for other plants:
http://www.greners.com/i/seed-starting-and-cloning/humidity-domes/mondi-7-mini-greenhouse.html
These are nice because they allow more airflow but you cannot get light as close with them. If you use something like that, make sure your tobacco seedlings get lots of light so they do not get leggy. Personally, I never use them for tobacco, I use the flat covers- tobacco seedlings do not grow fast enough to justify it.
I use similar soil plug inserts like those in the picture on the first link. I pay about $1.50 for a single flat's worth off the top of my head. I generally just stock up. I also reuse them.
For less than $10, this setup works very well for me and I get about 72 cells worth of plants out of it.
Another option I have done, skip the inserts all together and just put soil in the bottom flat, sprinkle your seeds on the soil and then thin out later and pot up the individual seedlings in their own pots. Just be careful when moving the young seedlings between flats/pots.
As far as pellets. IMO, they are a total waste of money and largely ineffective. First time I grew tobacco, I used them and had problems (I have successfully used them with some other plants just fine, but prefer to use soil now). Really, at the end of the day they are basically just pressed peat moss with some super absorbent chunks mixed in (at least I believe that is the case). I typically just use a fine potting soil- usually peat based rather than mulch based. If you are hell bent on using some kind of individual pre-made germination media like that, Personally, I would suggest something like rooting plugs over Jiffy pellets (I have a hydroponics friend that has grown tobacco successfully in rockwool in a hydroponic system. Last time I grew tobacco hydroponically, I think I may have used rooting plugs inside hydroton balls)- you can usually find these at hydroponics stores and occasionally elsewhere. Again though, these are expensive and personally, I am not sure that there is much benefit over just plain potting soil- assuming you are reasonably hygienic about your soil.
A key thing to remember is not to cover the seeds, and water from below or with a sprayer until they get a little bigger. Also, do not leave the humidity dome on for too long as it will soften your plants. If you do, make sure you "harden them off"- which just means over the period of a week or so, slowly open the lid more and more to give your seedlings an opportunity to get used to your ambient humidity. If you do not, it could shock them.
So, to summarize (based on the title of the thread, I am making the assumption here that you are new to starting these seeds):
1) Use a fine potting soil if possible- especially if starting in cell packs
2) Do not cover the seeds- make sure the sown seeds get good light- even before germination.
3) Water from below in the bottom tray- allowing the water to "wick up" through the soil plugs. If you need to be moistened from the top (IE they ran out of water or something and need hydration fast) use a fine mist garden sprayer until they are large enough to not get washed away with other forms of watering.
4) Take the humidity dome (if using) off of the tray when seedlings start to emerge, or shortly thereafter. If you wait a little too long, do not take it off immediately, prop it open slowly over the period of a week or so.
