No, it's not weird at all to want someone to come along with you to buy female clothing, things like these are big steps and it's perfectly normal to be nervous - I certainly was on my initial transition-related shopping trip. It might only be for the first few times that you'll need that person there, though - as you grow more accustomed and confident, it'll be a lot less nerve-wracking.
I literally just google 'trans groups in *my city*' and try to attend as many as I can find, at least once. Every group is a bit different, there definitely are the more activism-centered ones versus others that are just relaxed social spaces to meet people and share resources. There are plenty of genderqueer-but-not-trans identified people in these spaces.
I haven't looked into LGBT
groups nearly as much, so I wouldn't be able to help you on that one. I have heard plenty of complains from the diehard activists at one of the groups I do regularly attend, about the 'T' often being ignored by 'LGB' people in their own activism - but that's about it. It's worth trying out, though.
I'm a little confused by the last part of your question. Queer, from my understanding, can include bi- and pansexuals as well. Unless you are talking about genderqueer? - That's quite different. Gender identity and sexuality are independent of one another. Nonetheless, no matter whom you date, it's all okay.