You will find that you will like entirely different flavors than you thought you would. Vaping and smoking are similar but different at the same time. Everything you think you will like, you probably won't, and everything you think you will hate, you will probably love! And then, in a few weeks, your tastes will change again and you will like even more new things, and you might not like the juices you like now.
If you are lucky enough to have a brick and mortar store nearby, start there because they usually let you test all of the flavors before you buy any. And if not, find a company that offers sample packs of flavors, and try to get a decent variety.
If you are dead set on trying tobacco flavors...HHV and Halo are pretty popular. From HHV, Gandalf is probably most popular, and from Halo, I see Tribecca the most probably...followed by torque.
http://www.heathersheavenlyvapes.com/store3/
http://www.halocigs.com/
But if you find that you don't like tobacco as much as you thought you would...
Alice in Vapeland- they sell 5 juice sample packs, as well as a huge sampler of EVERY flavor.
www.aliceinvapeland.com
Highbrowvapor- they have a few tobacco flavors that get good reviews, but I think they shine in fruit and dessert flavors.
www.highbrowvapor.com
Fancee Juice- they also sell a sampler...
www.fanceejuice.com
Mister E liquids- Not sure if they have sample packs, but if you like throat hit, their juice called Grey Matter has one of the biggest throat hits I have encountered. Jade tiger is a pretty good one too.
http://www.mister-e-liquid.com/categories/Our-Handcrafted-E%2dLiquid/Mister-E's-House-O'-Flavor/