I'm not sure if there's a specific label for guys who like girls with dicks, but the phenomenon itself isn't that weird. If you think about it, the whole dominant/submissive spectrum isn't just a gay person thing - straight guys have varying levels of it too. I imagine that the attraction comes from the desire to be the "bottom" in that relationship, yet you'd still be straight. In other words, the transgendered man to you is a girl with a strap-on.
If you're talking about being the "top" in a relationship with a transgendered man though, I think that would definitely no longer qualify as straight. Whether or not the man in question has silicone in their chest or a wig and makeup on, they still are a man, and I don't see why you'd be more attracted to them than you would be to a normal woman as a heterosexual man.
All that said, it could easily just be a fetish or a bi-curiosity. Assuming that you're talking about yourself, if you're straight but also are attracted to transgendered men, don't worry about labeling yourself. There are a bunch of strange combinations of sexuality, like straight cross-dressers etc., and it just provides further testament to the idea that sexuality is a spectrum and that one should just like what they like without stressing out too much over it :P
I see a problem with you post, although it is open-minded, in that you make a lot of misconceptions that are borderline offensive to some people.
Even if you meant well it will be good for other readers to provide further clarification (anyone else feel free to add to that).
First paragraph.
No idea why you are portraying domination and submission primarily as a "gay person thing".
In a gay male relationship, there may be domination/submission play in the bedroom, but that doesn't mean the dominant role is restricted to the "top guy". Besides, just as a safe reminder, in many gay relationships there is no such play. There isn't even a "top" and a "bottom". Some guys prefer to always assume the same of these two positions regarding penetration, but in a lot of gay relationships it just varies from one love-making session to the next.
Don't equate "dominant/submissive" with "top/bottom" and boil it all down to "Who owns the penis?", thank you.
Second paragraph.
Transgendered or transsexual persons have assumed at least the other gender (the other sex too if they have gone through with a sexual reassignment operation), and in general prefer to be referred to under their new gender. If a man has completely assumed the opposite gender, then for all intents and purposes it is a very debatable question where you should still call them a man, thus questioning your use of "transgendered man" here.
There are many, many degrees in how far one assumes another gender, so please refrain from assimilating a "transgendered man" as someone who wears a wig and makeup. It sounds like you are equating transgendering with transvestism.
I am sorry but on this matter it is very important to watch your semantics. There is an ongoing semantical debate among people who are far more involved with these issues than I am, so I don't think there is any defined "right" way to talk about transgendered and transsexual persons that no one will ever take offense with. Still, you could have been more careful with your phrasing to offend
less people, myself included.