In terms of clothing, some very tasteful examples were posted by VandalSquirrel in another thread. These would be dresses that would be appropriate for preference night at Texas and most other schools:
http://www.greekchat.com/gcforums/sh...ad.php?t=97970
The Texas 2008 Greek Guide is available online here:
http://deanofstudents.utexas.edu/gle...s/GrkGde08.pdf
The Texas Panhellenic council website is here:
http://www.texaspanhellenic.org/index.htm
You can download the 2008 Panhellenic Recruitment booklet here:
https://webspace.utexas.edu/rau64/Re...f?uniq=-9dd49l
The clothing suggestions begin on page 20 of that booklet. Definitely follow their suggestion about packing a pair of comfy flip flops to walk between houses in.
Overall, in terms of clothing, I would focus less on specific brands and more on overall style and elegance.