Well it really depends on what you are looking for. If you are looking for another vampire show with humor Buffy the Vampire Slayer is really good, but it is a young adult show so it isn't as mature as True Blood. If you are looking for a more Mature show Carnivale that was also on HBO is a great show. If you want a show that covers everything supernatural then and also has humor, drama, and really nice looking guys then Supernatural is the show for you. I am not really sure what type of Supernatural show you are looking for.
If you want to check out Supernatural there is a viewing party that we have going on here. There are links to the full episodes on the spot. There are plenty of fans there that can answer questions about the show also. I have also included the commercial for this spot. Here is a link to the spot.
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Also, I started a spot dedicated to shows of this nature. On it is a list of all the past and present shows that are sci-fi and horror/supernatural. Here is a link to that list.
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