Thank you everyone for your wonderful responses! It is very helpful just to hear about the different avenues people have for being invited to events. I felt like this might have been a really silly question, but am so happy to see how much info everyone gave!
I'll start off by addressing some of the questions/concerns:
I am 25 and don't really have access to those kinds of friends/family (or funds!) but am hoping to create/cultivate an engaging lifestyle for myself and my husband that would include meeting new people, volunteering, and becoming more involved in our new community.
I am not interested in solely dressing up or social climbing. I have volunteered for years, and having gone to an arts school myself, relish and appreciate the arts in all forms. I am also interested in human rights and environmental issues, so being passionate about charity causes would be quite honest for me. I would also like to make friends with similar people.
ellyabillion - There is a junior league in northern Virginia, I will email and see what their policy is for new members, but from their website it sounds like a great way to get involved in my area, thanks for the tip!
voguette - Your experiences sound so amazing, thanks for sharing! What you have described is what I am hoping to accomplish, meeting people with similar interests which then leads to more enriching experiences.
I will also follow your advice in regards to gowns, I know my grandmother did that with her outfits, her closet was full of notes describing where she was, who else was there, and what she wore.

homeschoolmama22 - I will check out the avenues you mentioned, museums are right up our alley!
leesa17 - I can imagine you would need alot of money to keep that up. In the future hopefully we will be able to contribute like that.
garnetsue - yes the universal casual aesthetic seems to be taking over everything, and I so long to be able to dress glamorously!
kitsmommy - I will keep in mind work related avenues, that's one that hadn't occurred to me yet.