Here is a start to answering some of your questions. . .
Can I take a regular bra and make it into a bellydance costume masterpiece?
yes. But read the thread we had here about a week or so ago about making bras. Lots of really good info on that.
How do you go about making a belt?
You draft a pattern, adjust and then make it. Usually you need a couple of layers of fabric including what ever you are using for the 'outter' to give it some body and the streangth to hold hte beads or what ever you are putting on it.
First steps in making skirts (mermaid, gypsy, circle) and harem pants?
once again, the first step is drafting a good pattern. Or finding one. Although circle skirt info is easy to find on the net.
I was actually looking at info on all of these which I had downloaded from Belly Dancing -- Art Of Middle Eastern Dance -- Bellydancing in Iowa City. Shira has worked with DinaLydia, aka the Costume goddess. you should check it out!
Can someone with cultural knowledge give me a basic guide in different styles of bellydance costumes and the characteristics of various cultures?x
Although this will seem a little triate, and know that this is changing alot, here goes:
Turkish costumes have shaped belts and bras. 2 pieces. V fringe. They are generally light weight with lots of cut outs.
Egyptian costumes are usually straight across the front and have a scooped or cupped back to the belts. Fringe is usually short. Also usually heavy.
Two piece are pretty new. Both Turkish and Egyptian do them.
Caberet Dresses are pretty musch an Egyptian invention because of their modesty laws, but there are some lovely ones coming out of Turkey as well.
Lebanese costumes are interesting to me. Genereally full skirts with a short skirt underneath and a lot of leg. Lebonese dancers also seem to be in love with plaqtform heels.
American Cab can be jsut about anythings from beads to coins and a combo (my favorite Amcab bedlah is a vintage gold coin costume made from basically quartes, with chianette fringe and a layer of egyptian fringe. Paired with 2 or three layered 3 panel circle skirts, heaves!) Lots of skirts, lots of layers of fabric. And many times lots of leg.
tribal - Depends on the look and what kind of tribal you are dancing.
Comeon everyone, jump in. I am not the last wordin this.
{{{HUGS}}}